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Chem PPT Flashcards, Unit 1
Hospital laboratory providing all high-volume and emergency testing is ___.
Core laboratory
Laboratory medicine is a component of
Laboratory Science
Laboratory medicine is involved in the selection, provision and interpretation of ___ and ___.
Diagnostic testing and individual specimens.
Laboratory testing is a process conducted in a ___.
Clinical laboratory
Laboratory testing is used for the following purposes:
Rule a diagnosis in or out, select and monitor disease treatment, provide a prognosis, screen for a disease, determine the severity of and monitor a physiological disturbance.
Molecular diagnostics is the use of molecular biology techniques for the following reasons:
Prevention, diagnosis, follow-up or prognosis of a disease and selection, optimization, monitoring of therapies.
In the clinical laboratory, the purpose of quality control is:
Proficiency testing, auditing, Benchmarking, Clinical governance
Which 3 facets of laboratory medicine can be attained with the use of telemedicine and tele-healthcare?
1. analytical testing2. use of clinical decision making informatics
What are some of the tools and methods in clinical chemistry that are now used in other areas of laboratory medicine?
- chemical testing- genetic testing- molecular testing- cancer diagnostics- infectious disease testing- identity testing
What is the purpose of molecular diagnostics?
For prevention, diagnosis, prognosis, follow-up of disease.
What does PCR stand for? Polymerase chain reactionWhat are ethics? Are the rules or standards governing the conduct of an
individual or the members of a profession.What are ethical issues in laboratory medicine?
Confidentiality of genetic informationConfidentiality of patient medical informationAllocation of resourcesCode of conductPublishing issuesConflict of interest
What are confidentialities? Genetic informationPatients’ medical information
What is allocation of healthcare resources?
Best use of timeCost vs. quality
What are publishing issues? Fraud
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PlagiarismFalsification/fabrication of dataConflicts of interest
What is the future of laboratory medicines?
Full of promise but also challengesExplosion of insight into disease and treatmentResponsibility to stay up to date and behave ethically
What are the role of guidelines in method evaluation?
Clinical and Laboratory Standard Institute.International Organization for Standardization (ISO)Meeting laboratory accreditation requirements.
What are the medical usefulness criteria?
Turnaround time.Clinical utility.Sensitivity.
Specificity.What are the analytical performance criteria?
Precision.Accuracy (trueness).Analytical range.Detection limit.Analytical specificity.Instrumentation.
Other practical criteria are: Principle of the assay and protocol for performing the test.Composition and stability of reagents and reference materials.Technologist time and required skills.Possible hazards and appropriate safety precautions.Specimen / instrument requirement and limitations.
What is a Frequency Distribution
a table that displays the frequency of various outcomes in a sample, these entries on the table contain the count of occurrences of what is being measured within a particular group, displaying the distribution of values in the sample.
What is a Histogram a graphical device for displaying a large set of data.What is a Nonparametric Approach to statistics
Statistics not based on parameterized distributions. in other words this type of statistics has no dependence on a specific set of parameters.
What is a Population is the complete set of all observations that might occur as a result of performing a particular procedure according to specified conditions.
What is a Sample group of observations that has actually been selected from the population. There is a need for proper selection of sample
How many pieces of data are needed to begin developing reference ranges.
20
True or FalseProbability and Probability Distributions do not require a large sample size to be accurate.
False, a large sample size is required for accuracy of probability and probability distribution. A large sample size will provide many data in which to form different conclusive statements.
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What are Parameters? 1) Descriptive measures of a populationIt is a constant that describes some particular characteristics of a population.
What is a median? An alternative parameter that indicates the central tendency of a population, defined as the 50th percentile.
What is a population mean? The parameter most commonly used to describe the central location of a population
What is population variance? A parameter describing the dispersion of values about the population mean.
What is population standard deviation?
The positive square root of the population variance, frequently used to describe the population dispersion in the same units as the population value
What are statistics? 1) Descriptive measures of the sample.Values calculated from the observations in sample
What is random sampling? 1) Each member of the population has an equal chance of selection throughout the population.
Precaution to ensure random samplingWhat is the Gaussian Probability Distribution?
1) Symmetrical distribution of errorsParametric approach
What is an example of the Gaussian Probability Distribution?
-What is required for Gaussian distributions and is randomly used in significance tests.
Student t Probability Distribution
-What is the relationship between instrument signal vs. concentration of analyte? The precision depends on stability of instrument response for given analyte.
Calibration
-Closeness of agreement between large-series average and true values.-Evaluated by comparison of measurements given (field) method and a reference method.
Trueness and Accuracy
-This s caused by instrument or Drift
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reagent instability overtime so hat calibration becomes biased.-Must be closed to zero top ensure unbiased results.
Carryover
Referring to qualitative concept, definecloseness of agreement of mean value with “true value”.
Trueness
Referring to quantitative measurement, define a measure of the systematic error.
Bias
Referring to qualitative concept, what term defines repeatability (within run), intermediate precision (long term) and reproducibility (interlaboratory)?
Precision
Referring to quantitative measurement, define a measure of the dispersion of random errors.
Imprecision
Define closeness of agreement of a single measurement with “true value”.
Accuracy
Definition for comprising both random and systematic influences.
Error of Measurement
What is caused by instrument or reagent instability overtime so that calibration becomes biased?
Drift
What must be ensured in a carryover to ensure unbiased results?
Assay carryover must be close to zero.
True or False:Trueness is a qualitative concept.
True
Trueness is defined as closeness of agreement of _____ value with “true value”.
Mean
True or False:Precision is a quantitative measure.
False
Precision is associated with ___________ and __________
Repeatability and reproducibility.
Define Accuracy. Accuracy is a qualitative concept that is closeness of
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agreement of a single measurement with “true value”.A measure of the systematic error is _________.
Bias
A measure of the dispersion of random errors is defined as?
Imprecision
Error of measurement is defined as a quantitative measure that comprises both ________ and systematic influences.
Random
Define Precision. Closeness of agreement between independent results under set conditions
True or False:Imprecision of measurements is solely related to the random error of measurements and has no relation to the trueness of measurements.
True
Closeness of agreement between results of successive measurements carried out under the same conditions is defined as?
Repeatability
Define Reproducibility. Closeness of agreement between results of measurements performed under changed conditions of measurements.
______ refers to the relationship between measured and expected values over the range of analytical measurements.
Linearity
Presence of linearity is a prerequisite for a high degree of ________.
Trueness
What does analytical sensitivity mean?
Capacity of a method to detect small variations in the concentration of analyte
True or False: Analytical sensitivity is often expressed as the slope of the calibration curve.
True
Analytical sensitivity depends on the ratio between the _____ of the calibration function and the ______.
SD ; slope
What does analytical sensitivity depend on?
Precision of method
What are two other names for measuring interval, reportable range
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Analytical Measurement Range and Limits of Quantification?What is Analytical Measurement Range and Limits of Quantification?
analyte concentration range over which measurements are within declared tolerance for imprecision and bias of the method
What is Analytical specificity and interference?
Capacity of procedure to determine specifically the concentration of target analyte despite interferences
Give 3 examples of Analytical specificity and interference?
hyperlipemia, hemolysis, bilirubin, anticoagulants, antibodies, degradation products
What are 4 analytical goals? Based on principles and a hierarchyBased on biological variationGoals for biasRelation of goals to limits set by professional bodies
What are qualitative methods? Use in point-of-care testingClinical sensitivityClinical specificityGold standardIndependent reference method
How is comparison of measurements obtained?
yielded by two different methods
What are Parallel measurements?
a set of optimal patient samples
What is a Basic error model? Distinguishes pure, random errors from those related to incorrect calibration and nonspecificity of the assay
What are examples of basic error model?
Sample-related random biasCalibration bias (changed in lot number) and random bias (sample specific interferences)Mistakes or clerical errors
What is the method comparison data model?
It is comparison of a routine method with a reference method, and comparison of two routine methods
How is the planning a method comparison study?
-Distribution of analyte concentrations-Representativeness of samples•Samples from different patients categories•Storage and treatment of samples-Comparisons of measurements taken over days-Ethical aspects
What is the difference (Bland-Altman) plot?
Plot of differences against average results of methods
What is the difference (Bland-Altman) plot with specified limits?
Plot of differences in relation to existing method located within given specified limits
What is the regression analysis? Applied in comparing results of analytical method comparisons
What are 3 examples of Regression analysis?
1. Deming Regression Analysis2. Ordinary Least-Square Regression Analysis (OLR)
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3. Nonparametric Regression Analysis (Passing-Bablok)What is Traceability? - Means of ensuring agreement between measurements
from routine methods- Based on an unbroken chain of comparison
measurements leading to a known reference valueReference measurement procedure selected measurement procedure routine measurement procedure
What are some considerations for the Uncertainty Concept?
- Pre-analytical variation- Method imprecision- Sample-related random interferences- Calibration uncertainties
Bias correctionsWhat is Sensitivity? Percentage of people with a disease correctly predicted by the
testWhat is the formula to calculate sensitivity?
Sensitivity = True Positive / (True positive + False negative)
______ is the diseased individuals who are correctly classified by the test
True Positive
______ is the diseased individuals who are misclassified by the test
False Negative
What does specificity mean? Percentage of people without a disease correctly predicted by the test.
What is formula of specificity? TNSpecificity = ----------------
TN + FPTN (True Negative) stands for: nondiseased individuals who are correctly classified by the testFP (False Positive) stands for: nondiseased individuals who are misclassified by the test Following are description of what type of tests?- ) Having only positive or negative results and provide qualitative results.-) Have a single sensitivity and specificity pair for a designated assay cutoff
Dichotomous tests
Following are description of what type of tests?- ) produce quantitative results.- ) Have an infinite number of sensitivity and specificity pairs, as the cutoff varies from lowest to highest decision value.
Continuous tests
Name the test that is generated by plotting sensitivity (y-axis)
Receiver-Operating Characteristic Plots
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versus specificity (x-axis)?When using this test, plot displays same information graphically?
Receiver-Operating Characteristic Plots
Following are description of what type of tests?- ) Relative measure of test performance.- ) Test performance depends on region of curve (sensitivity vs. specificity) selected for analysis.
Receiver-Operating Characteristic Plots
Base on probabilistic reasoning, how ROC test should be interpreted?
Result should not be interpreted in isolation.
-) Necessity of viewing results through prism of the clinical setting, and- ) Interpretation tempered by knowledge of the prevalence of the disease should be considered in ROC curve according-----------------?
Probabilistic reasoning
What does prevalence mean? Frequency of a disease in the population under scrutiny.-------------Obtained with the use of several techniques?
Prevalence
What are the two types of predictive values?
Fraction of subjects with positive result having the disease in question; fraction of subjects with a negative result who do not have the disease
What are predictive tests used to for?
They are used to interpret dichotomous tests and continuous tests used in dichotomous manner
What are the three functions used in a predictive value equation?
Functions of sensitivity, specificity, and prevalence
What is the equation for the predictive value of a positive test (PV+)?What is the equation for the predictive value of a negative test (PV-)?What is the Odds Ratio (OR)? The probability of the presence of a particular disease divided
by probability of its absence.
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What does the Odds Ratio reflect?
It reflects the prevalence of the disease in thepopulation.
What is the Likelihood Ratio (LR)?
The probability of occurrence of a specific test value given that disease is present divided by the probability of same test value if disease were absent
What does LR stand for? Likelihood RatioWhat is the formula to calculate Positive likelihood ratio (LR+)?
Sensitivity/ 1- specificity
What is the formulat to calculate Negative likelihood ratio (LR-)?
Specificity/ 1- sensitivity
What is the LR for quantitative tests?
The tangent slope of ROC curve
When calculating LR, what is not considered?
Disease prevalence and other prior information
What adjustment is required before result is obtained?
For best estimate of probability of disease
What is Bayes’ Theorem? Permits calculation of disease probability after new information is added to existing data
How is Bayes’ Theorem applied to yield an odds ratio?
With the use of the likelihood ratio and odds ratio
What assumption does Bayes’ Theorem rest on?
Test independence
What is the formula for Bayes’ Theorem?
P(D/R) = Sensitivity x Prevalence/ Sensitivity x Prevalence + (1 Specificity) x (1 – Prevalence)
What is combination testing? Use of test panels to increase sensitivity and specificity or to decrease costs
Why is calculation of performance difficult with combination testing?
There is a need for test independence
Why is it not beneficial to add tests to a panel?
False positive rate is expected to rise
What is Combination Testing? Increased value of sensitivity over specificity if curable disease with low-cost therapy is diagnosed
Strategies for manipulating the order of testingOrder of testing does not affect performance but may affect costs
What is Sensitivity? Result with disease.What is Specificity? Result without disease.What are 2 Methods for Assessing Diagnostic Accuracy?
QUADASSTARD
What is QUADAS? Quality Assessment of Diagnostic Accuracy Studies
What is STARD?Standards for Reporting of Diagnostic Accuracy.
1. A project designed to improve the quality of reporting of the results of diagnostic accuracy studies.
What is Evidence-Based Term introduced in 1991
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Medicine? Conscientious, judicious, and explicit use of best evidence
Justifications for evidence-based approachEncourages innovation and change
What is evidence-based medicine (EBM)?
Application to laboratory medicine of the principles and techniques of EBM and clinical epidemiology
Ensures that the best evidence obtained is made available to assist clinician in making the best decisions for the patient, leading to increase probability of improved health outcomes
What is Evidence-Based Medicine and Laboratory Medicine?
Roles of diagnostic tests
What are the roles of diagnostics tests?
Scenarios of decision-making process, each involving a question, a decision, and an action. For, example:
Seeking a diagnosis Ruling out a diagnosis Making a prognosis Treatment selection and optimization Treatment monitoring
Will the diagnostic test leads to change in probability the presence of a disease?
Useful diagnostic test leads to change in probability of presence of a disease, but the change alone does not prompt the decision.
What will be the intervention after the primary diagnostic test?
Follow-up of testing with an appropriate intervention
How does the diagnostic test impact?
Value of test based on impact on patient’s health
Is diagnostic test safe? Harm done by restriction of researchWhat is the outcome? “Test and act”How many types are there in evidence-based laboratory medicine?
Five types of studies in evidence-based laboratory medicine
How is the first type in evidence-based laboratory studied?
Characterization of the diagnostic accuracy of tests by studying groups of patient
What is the outcome in evidence-based laboratory type 2?
Determination of the value of testing for people who are tested (outcome)
How accuracy of diagnostic studies in evidence-based laboratory type 3 are?
Systematic review of studies of diagnostic accuracy or outcome of tests to answer a specific clinical question
How does the type 4 in evidence-based laboratory be evaluated?
Economic evaluation of test to assess the economic value of using the test
What is included in evidence-based laboratory type 5?
Audit of performance of tests during use to answer questions about their use
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What other technique is used in evidence-based laboratory medicine?
Use of computerized modeling techniques to assess cost-effectiveness of tests and impact of process changes on resource utilization
What is the alternative design? It is results of patients known to have the disease are contrasted with a control group.
How many types of verification bias?
Two
What are the verification bias’ types?
Differential verification bias and Spectrum bias
What is the outcome studies? It is the results of medical interventions in terms of health or cost (clinical, operational, economic)
What is patient outcomes? It is the outcomes associated with patient’s condition and experience.
What is examples of patient outcomes?
Mortality, morbidity, complication rates, length of stay in the hospital, waiting time, costs of care, patient satisfaction with care
What is the usage of outcome study?
- Improvement of outcomes with improved test- Test as surrogate outcome marker- Value of operational and economic outcomes to care
providers, purchasers, and policy makers- Differentiation of outcome studies from studies of
prognosisTest attributes and studies of outcomes
What is the importance of outcome studies in medicine?
The requirement of proven effectiveness for drugs and the demand for effectiveness of diagnostic testing as well as to prove high quality care and show improved outcomes.
How do randomized control trials (RCT) work?
Patients are randomly assigned to receive either the intervention to be tested or an alternative and an outcome is measured.
What are RCTs? A standard for studies of health effects of medical interventions.
How are RCTs regulated? CONSORT (Consolidated Standards for Reporting Trials).What is the optimal design of RCTs?
It includes the evaluation of applicability of an outcome study.
What are the several defining features of systematic reviews of diagnostic testing?
The explicit methodology helps ensure reproducibility with multiple objectives, to answer strictly defined clinical questions in a way that minimizes bias.
What do systematic reviews of diagnostic tests require?
Time, multiple people with multiple skills anddatabase searches for previous studies?
What elements of protocol are there for diagnostic tests?
Title, background information, composition of the review group, a timetable, the clinical question(s) to be addressed in the review and a search strategy.
What are some systematic reviews of diagnostic tests?
1) Inclusion and exclusion criteria for selection of studies2)Methodology of data extraction and data extraction forms3)Methodology of and checklist for critical appraisal of studies4)Methodology of study synthesis
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What are some key steps in a systematic review of a diagnostic test?
1) Identify the clinical question.2) Define inclusion and exclusion criteria.3) Search the literature.4) Identify relevant studies.5) Select studies against explicit quality criteria.6) Extract data and assess quality.7) Analyze and interpret data.8) Present and summarize findings.
What are some strategies for search of primary literature?
1) An electronic search of literature databases2) Hand searching of key journals3) Review of the references of key review articles
What is essential to do with quality review and data extraction?
Identified papers should be read independently by two persons and data extracted according to a template
Who should the data be summarized and presented?
1) Presented in tables2) Data should include sensitivities, specificities and likelihood ratios3) Summarized in plots that provides an indication of the variation among studies4) Should also include an assessment of the quality of each study using a scoring system such as QUADAS (Quality Assessment of Diagnostic Accuracy)
What are some benefits of using meta-analysis for multiple studies?
1) Statistical way of analyzing data from multiple studies2) Explore sources of variability in the results of clinical studies3) Increase confidence in the data and conclusions4) Signal when no further studies are necessary
What is the Influence of laboratory testing on healthcare costs?
Costs of laboratory testing have a profound effect on medical decisions
How to work on Hierarchy of evidence ?
technical performance → clinical performance → clinical effectiveness → economic sense
What is the definition of Cost-minimization analysis?
Simplest type of economic evaluation that compares the costs of alternative approaches that produce the same outcome
What is the definition of Cost-benefit analysis?
Determines whether the value of the benefit exceeds the cost of the intervention and therefore whether the intervention is worthwhile.
What is the definition of Cost-effectiveness analysis?
Looks at the most efficient way of spending a fixed budget to achieve a certain goal
What is the definition of Cost-utility analysis?
Focuses on the quality and the quantity of the health outcome
What are the Perspectives of Economic Evaluations?
-Patient-Provider-Payer (government health agency or health insurance company) Society
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What is the definition of silo budgeting?
The laboratory budget is usually “controlled” independently of the other costs of healthcare
What are the clinical practice guidelines?
Tool for facilitating implementation of findings of primary studies and systematic reviewsTo assists practitioner and patient decisions about appropriate healthcare for specific clinical circumstancesNeed for transparency to ensure integrity
What are the Steps in developing guidelines?
-Topic selection-Establishment of target group and development team-Identification and assessment of evidence-Transformation of evidence into guideline-External review and updates to guidelines
What is the definition of Audit? Refers to the review of case histories of patients against the benchmark of current best practice
What is Clinical Audit? Benchmarking of performance with performance indicators against performance of peers
What are the advantages of Audit cycle?
-Problem-solving-Monitoring of workload and demand-Monitoring of new tests-Monitoring variation between providers and adherence to best practices
How do you apply the principle of Evidence-Based Laboratory Medicine in Routine Practice?
• Principles support manner in which laboratory medicine is practiced
• Principles provide logic• Means of providing high-quality serviceUse is more complex for laboratory than for clinical medicine but still critical
What do reference values mean?
Results of certain type of quantity obtained from a single individual or group of individuals corresponding to a stated description, which must be spelled out and made available for use by others.Also referred to as observed values, reference interval, reference limit
What are the mandatory conditions in the establishment of Reference Values?
All groups of reference individuals should be clearly defined.The patient examined should resemble sufficiently the reference individuals in all respects other than those under investigation.The conditions under which the samples were obtained and processed for analysis should be known
What are the mandatory conditiions in the establishment of Reference Values?
• All quantities compared should be of the same type.• All laboratory results should be produced with the
use of adequate standardized methods under sufficient analytical quality control
• The clinical sensitivity, clinical specificity and prevalence in the populations tested should be known.
What are the criteria of • Criteria should include:
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selection of reference individuals?
• Statements describing the source population• Should be randomly selected
• Specifications of criteria for health• The disease of interest
What type of procedures are recommended taking into account the requirements that will enable all the constituents under study to be measured accurately?
Standardized
What requires preanalytical standardization?
1. Preparation of individuals before sample collection2. The sample collection itself3. Handling of the sample before analysis
A total of twenty (20) samples from reference individuals should be analyzed and ensuring that no more than how many values for the QC fall outside the proposed limit.
2
Considerations will include what?
a)Analysis methodEquipment, reagents, calibrators, types of raw data, calculation methodb)Quality controlc)Reliability criteria
What are the Statistical Treatment of Reference Values?
I. Partitioning of the reference values into appropriate groups
II. Inspection of the distribution of each groupIII. Identification of outliersDetermination of reference limits
Partitioning of the reference values into appropriate groups is also known as?
stratification (strata), categorization (category), or subgrouping (subgroup or partition)
Reference values can be partitioned according to what?
Sex, age, and other characteristics
Statistical Treatment of Reference Values will give rise to narrower and more appropriate ______?
reference intervals
Examples of Partitioning Criteria for Possible Subgrouping of the Reference Group are?
Age, Gender, Genetic Factor, Physiological Factor, and other factors like socioeconomic, environmental and chronobiological
What is important to do have an accurate presentation of an observed value in relation to
To have as much information provided as is possible.
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reference values?What observed values are recorded in relation to reference values?
Low, usual, and high
What mathematical equation that measures distance is used in reference ranges?
Standard deviation
Give 2 examples of a subject-based reference value problem.
Inherent to population-based (Fig. 5-3)Use of subject’s own previous healthy values as reference for future values
Name 5 things that are true of transferability reference values.
Determination of reference values beyond the scope of many laboratories; transfer solves problem
Must be comparable populations Steps to ensure comparable analytical methods Use of pooled multicenter data1. Importance of verifying “borrowed” values before use
What is clinical sensitivity? Fraction of subjects without the disease that assay correctly predicts
What is clinical specificity? Fraction of subjects with disease that assay correctly predicts
What is Predictive value? Combination of disease prevalence with sensitivity and specificity
What is Prevalance? The proportion of study population with diseaseWhat are examples of s Subject-Based reference values be used as a reference value?
The use of subject’s own previous healthy values as reference for future values.Problems inherent to population-based reference values are encountered.
Usage of reference values generated by other laboratories is an example of what kind of reference values?
A Transferability of reference values
The Use of Transferability of reference values can be any of the followings except:
a. Steps to ensure comparable analytical methods (identical calibration, quality control results
b. Importance of verifying “borrowed” values before use
c. Expressing observed value by a mathematical distance measure (e.g., standard deviation)
C
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d. Use of pooled multicenter data
What is Clinical sensitivity? A fraction of subjects with disease that assay correctly predictsA fraction of subjects without the disease that assay correctly predicts is a clinical:
a. Clinical sensitivityb. Clinical specificityc. Predictive valued. Prevalence
B
What is the difference between Predictive value and Prevalence?
A Predictive value is a combination of disease prevalence with sensitivity and specificity while a Prevalence is a proportion of study population with disease
Name the six types of body fluids that may tested in the lab:
Cerebrospinal, synovial, pleural, amniotic, ascitic and pericardial fluids.
In addition to whole blood, what are the five types of biological specimens collected for lab testing:
Serum, plasma, urine, feces, saliva.
The agency responsible for publishing and procedures for standardized specimen collection is:
The Clinical and laboratory Standards Institute (CLSI)
The liquid portion of clotted blood is:
Serum
Serum contains fibrinogen: True or False?
False
The liquid portion of anticoagulated blood is:
Plasma
Plasma contains fibrinogen: True or False?
True
What are the 3 layers of centrifuged plasma:
Bottom is RBCs, Top is plasma and slim middle buffy layer is WBCs and platelets
What does K3EDTA stand for? Tripotassium ethylenediaminetetraacetate
What does K2EDTA stand for? Dipotassium ethylenediaminetetraacetate
What are K3EDTA and K2EDTA?
Anticoagulants
How does K3EDTA and K2EDTA prevent coagulation?
By removing ionized calcium
What is this process called? Chelation
What is the color code for EDTA?
Lavender, occasionally pink or white
What is the most commonly used anticoagulant in hematology for complete blood count or any of its component
EDTA
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tests?What does CBC stand for? Complete blood count
What are the component tests for CBC?
Hemoglobin, packed cell volume, total leukocyte count, leukocyte differential count, platelet count
What does ESR stand for? Erythrocyte sedimentation rat
What is EDTA used for in blood banking?
Blood grouping, rH typing, and antibody screening
EDTA is useful for isolation of genomic DNA and qualitative and quantitative virus determinations by molecular techniques.
True
EDTA inhibits certain enzymes like alkaline phosphotase, CK and leucine aminopeptidase.
TRUE
EDTA is unsuitable for calcium and iron analyses using photometric or titrimetric techniques.
TRUE
How does sodium citrate prevent coagulation?
By removing calcium and precipitating it into an unusable form
What color is the tube for sodium citrate?
Light blue
Which tests use sodium citrate? APTT, PT, Westergren ESR
What is the ratio of sodium citrate to blood?
1 part anticoagulant to 9 parts blood
What is ACD? Acid citrate dextrose
Why is ACD ideal for molecular diagnostic and cytogenic testing?
Its ability to preserve both form and function of the cellular components
Which anticoagulant forms insoluble complexes with calcium ions?
Oxalate
At what concentration will oxalate cause hemolysis?
Greater than 3g oxalate/liter of blood
What substance inactivates blood-clotting factor thrombin and factor Xa?
anti-thrombin
What is the recommended form of heparin?
Lithium heparin
What is the color code for heparin?
Green
What is the only anticoagulant that should be used for the determination of pH, blood gases, electrolytes, and ionized
Heparin
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calcium?Which enzyme converts fibrinogen to fibrin?
Thrombin
Why is thrombin used in “stat” serum testing?
Its short clotting time
Which dry additive is a weak anticoagulant and is primarily used in preventing glycolysis?
Sodium fluoride
Which 2 substances are effective at 2g/L of blood concentration?
Sodium fluoride and potassium oxalate
What is a potent inhibitor of urease?
Sodium fluoride
What are the methods of specimen collection?
1. Venous Blood Collection (Phlebotomy or Venipuncture) Syringe Method Vacutainer or Evacuated Tube Method2. Capillary or Peripheral Blood Collection (Skin Puncture)3. Arterial Blood Collection (Arterial Puncture)
What are supplies and equipment of venipuncture by syringe method?
Test requisition Tourniquet and disposable gloves Sterile disposable syringe with needle Alcohol swabs (70%) and gauge square pads Adhesive plastic strips
What are supplies and equipment of venipuncture by vacutainer method?
Test requisition Tourniquet and disposable gloves Sterile disposable needles and needle holder Various evacuated blood tubes Alcohol swabs (70%) and gauge square pads Adhesive plastic strips
What are the sites of venous blood collection?
Veins on the anticubital fossa region:1. Cephalic vein2. Basilic vein3. Medial cubital vein
Median vein of the armWhat are the sites of Venous Blood Collection?
Cephalic vein.Basilic vein.Medical cubital vein.Median vein of the arm.
What are the recommended order of draw for multiple specimen collection?
YellowRoyal BlueClear/RedLight BlueGold/RedRed/red, orange/yellow, royal blueGreenRoyal blue
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Lavender, pearl white, pink/pink, tan (plastic)GrayYellow (glass)
What are the methods of blood collection?
Patient identification.Personal protective equipment.Queries regarding fasting, medication.Proper positioning and vein and site selection.Appropriate needle, tubes, and other equipment.Timing of collection.Effects of tourniquet and stress.
What are the methods of capillary or peripheral blood collection?
Test requisition.Disposable gloves and sterile small gauze squares. Sterile disposable lancets.Alcohol swabs (70%) and gauge square pads.Equipment specific for the test ordered (glass slides, micropipette, and diluent, hematocrit tubes)
True or FalseSkin punctured blood is more like arterial blood than venous bloodA.TrueB.False
A
Possible times when one would perform the skin puncture technique for a blood sample rather than filling a tube might include:A.Sample volume is limited (eg. pediatric patients)B.Severe vein damage due to repeated punctureC.Burn patientsD.All of the above
D
Which of the following is not a proper site for skin puncture?A. earlobeB. plantar or lateral surfaces of the infant’s heelC. thumbD. big toe of infants
C
If a phlebotomist is performing a skin puncture on a finger and the fingers are cold and white due to low blood circulation, what is the proper method for increasing blood flow?
D
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A. Massaging finger by gently squeezing between thumb and forefinger.B. Rubbing finger briskly between hands.C. Warm the hand by holding it under very hot hot water for 10 minutesD. Warm the area with a warm, wet washcloth or heel warmer for 3 minutesWhy should a heel stick never be performed on the center of the heel?A. Because the baby may cry.B. The heel bone may be injured.C. The parents may become upset.D. It's ok to perform a heel stick in the center of the heel.
B
Blood collected from the radial artery of the wrist, brachial artery of the elbow, and femoral artery in the groin is called..A. Venous bloodB. Arterial bloodC. Capillary bloodD. None of these
B
Which type of blood vessel is used for blood gas analysis?A. VeinB. CapillaryC. ArteryD. B and C
D
True or FalseAnybody is allowed to perform an arterial puncture to obtain blood for blood gas analysis.A. TrueB. False
B
True or FalseSkin puncture is more like venous blood than arterial blood.
B
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Chem PPT Flashcards, Unit 1
A. TrueB. FalsePCO2 of venous blood is about _____ higher than in arterial blood.A. 1-2 mm HgB. 11-12 mm HgC. 6-7 mm HgD. 5-6 mm Hg
C
Glucose of venous blood is about 7 mg/L ____than skin punctured bloodA. moreB. less
B
Skin punctured blood is more prone to contamination by..A. bacteriaB. interstitial and intracellular fluidsC. dirtD. all of the above.
B
What is Hemolysis? 1) Disruption of the red cell membrane, resulting in the release of hemoglobin.
Hemoglobin concentration exceeds 50mg/dLWhat is in vivo hemolysis? Consequence of intravascular eventsWhat is in vitro hemolysis? Subsequent to or during blood collectionWhat are the causes of in vitro hemolysis?
1) Alcohol left on the skin2) Use of small bore needles3) Underlying red cell disorders4) Extreme temperature during transport
Other causesWhat are the effects of hemolysis?
1. False increase in the concentration of plasma lactate dehydrogenase, potassium, magnesium, phosphate and serum inorganic phosphate
2. Additional band caused by hemoglobin may be seen on serum protein electrophoresis (SPE)
3. Interferes with colorimetric methodologies4. Interferes with the amplification reaction of reverse
transcriptase in molecular diagnostic testing
What is Urine used for? 1) Aside from routine urinalysis, can be used for bladder cancer screening and monitoring of therapy for bladder cancer
2) Used for molecular testing for infectious agents (Chlamydia) or BK virus.
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What is part of taking a urine sample?
Necessity of cleaning patient’s genitalia before each voiding to minimize transfer of surface bacteria to the urine.
What are the types of urine specimens?
1) Type of specimen depends on test2) Untimed urine specimen (random)3) Clean, early morning, fasting specimen is most
concentrated and ideal for microscopic examination and detection of abnormal quantities of constituents (e.g. chorionic gonadotropin)
4) Double-voided specimen – excreted during a timed period after complete emptying of the bladder (glucose tolerance test)
5) Forensic studies specimen – testing for the presence of alcohol or drugs of abuse collected under rigorous conditions requiring chain of custody documentation
6) Catheter urine specimens – for microbiological examinations
7) Suprapubic tap specimen – sterile specimen for microbiological examination (culture) on infants
8) Timed specimen (4-, 12- or 24 hours)-Need for prolonged collection period to minimize the influence of short-term biological variations-Importance of adherence to instructions (diet restrictions, first urine is discarded, avoid fecal contamination)
What is another part of taking a urine sample?
Need for mixing of specimen because of variations in specific gravity, volume, and composition throughout the collection period
-The purpose for this in urine is to reduce bacterial action, reduces chemical decomposition and solubilize constituents that might precipitate out.
Urine Preservatives
-Immediately after collection, this is the most acceptable way of storage.-The act or process of making something sour (acidifying), or changing into an acid. This can cause precipitation of urates (unsuitable for uric acid determination).
Refrigeration.
Acidification
-In urine preservatives, what is used to reduce pH level?
Sulfamic asid (10 g/L urine)
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Chem PPT Flashcards, Unit 1
-What causes precipitation of urates?-What two preservatives are used to preserve porphyrins, urobolinogen and uric acid?
Boric acid (5 mg/L of urine)
Sodium bicarbonate or sodium hydroxide
-What type of sample is used to detect “parasites and ova” and “Occult blood” or presence of hidden blood for discovering the presence of a bleeding ulcer or malignant disease in the gastrointestinal tract (GIT). This type of sample is also used for meconium testing in the newborn’s feces to detect from maternal drug use during the gestational period.
Feces
-This type of specimen is used for the screening for trypsin activity from infants to detect cystic fibrosis, used to characterized the a type of porphyria and also used to determine nitrogen and fat in a 72 hour specimen used to assess the severity of malabsorption.
Feces
-This specimen is obtain from the lumbar region of the spine, and occasionally from cervical region, or from the cistern or ventricle of the brain. Used to rule out meningitis and demyelinating disease.
Cerebrospinal fluid (CSF)
-What lumbar locations is the CSF obtained from?
L3, L4 and L5
-Who is authorized for the collection of cerebrospinal fluid?-What departments do the fallowing sterile CSF tubes belong to:Tube #1, #2, and #3
A physician
Tube #1-Chemistry and SerologyTube #2-MicrobiologyTube #3-Hematolgy
CSF glucose is simultaneously ran with what kind of test?
A blood glucose test
True or false? False
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Antoglycolytic agents are added to CSFWhat can CSF give rapid identification of ?
Infectious agents
In molecular diagnostics CSF can also be used for what kind of cells (2) rearrangement associated with hematologic malignancies?
T-cell and B-cell
What is synovial fluid? Joint fluid that lubricates a joint, tendon sheath or bursaWhat is arthrocentesis? Surgical puncture to remove synovial fluidTrue or False?The technique of arthrocentesis depends on location and size of joint
True
What can synovial fluid be used for?
To indicate and aid characterization of the type of arthritis
What kind of tube should be used for synovial fluid?
A sterile tube with or without preservative (depending on test to be performed)
What kind of tubes should be used for synovial fluid for culture, glucose and protein?
Sterile plain tubes
What kind of tube should be used for total leukocyte, differential and erythrocyte counts for synovial fluid?
EDTA tubes
Synovial fluid can be used to detect the presence of ________ ___________.
Infectious microorganisms
What is a causative agent of Lyme disease?
Borrelia burgdorferi
Staphylococcus aureus is a causative of what kind of infection?
Staphylococcal infections
What kind of bacteria is Salmonella, Pasteruella and Pseudomonas?
Aerobid Gram-negative bacilli
What is amniotic fluid? Liquid contained by the amniotic sac of a pregnant womanWhat term is used to describe the collection of amniotic fluid?
Amniocentesis
True or false?Amniotic fluid can be used to indicate prenatal diagnosis of congenital disorders
True
True or False?Amniotic fluid can be used to
True
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Chem PPT Flashcards, Unit 1
indicate and asses in fetal lung maturityTrue or False?Amniotic fluid can’t be used to look for RH isoimmunization of intrauterine infection
False
What kinds of disorders can amniotic fluid diagnose?
Cystic fibrosis, sickle cell anemia, Tay-Sach’s disease, and thalassemia
How is chorionic villi removed?
With a catheter or needle
When is chorionic villus usually removed?
During gestation (early pregnancy)
How is chorionic villus observed?
Under the microscope for quality, quantity, and integrity
What kind of characteristics are you looking for in chorionic villi?
The quality of branching, budding, veining, and evaluation of maternal cell contamination
True or False?Chorionic villi has the same chromosomal and genetic makeup identical as the fetus
True
What is chorionic villi used to test for?
Inherited genetic disorders
What is serous fluid? Fluid that lubricates the opposing parietal and visceral membrane surfaces
What may an accumulation of serous fluids indicate?
Inflammation or infection
What can be differentiated using serous fluid?
Whether fluid is an transudate or exudate using protein or enzyme content analysis
What is the method of collection for serous fluids called?
Paracentesis
Chorionic villi has the same chromosomal and genetic makeup identical to what?
as the fetus
What is chorionic villi used to test for?
inherited genetic disorders
What is serous fluid? Fluid that lubricates the opposing parietal and visceral membrane surfaces
Accumulation of serous fluid may signify what?
inflammation or infection
How to differentiation whether fluid is an transudate (effusion) or exudate?
using protein or enzyme content analysis
What is the general method of collection?
paracentesis
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Chem PPT Flashcards, Unit 1
What cavities contain serous fluid?
Peritoneal cavity, Pleural cavity, Pericardial cavity
The fluid contained between the visceral and parietal membrane is known as what?
the Peritoneal Fluid
Pleural fluid is contained between what?
Visceral space and pleural space
Pericardial fluid is located where?
Around the heart
What is thoracentesis? Collection of pleural fluidWhat is Peritoneocentesis? Collection of peritoneal fluidWhat is Pericardiocentesis? Collection of pericardial fluidHow is the method testing of saliva?
Measure of blood group substances to determine secretor status and genotype
What are buccal cells? Are cells of the oral cavity, excellent source of DNA.Collected by rinsing with mouthwash and using swabs or cytobrushes.
What is the solid tissue? Breast cancer tissue, testing for estrogen and progesterone receptors and have to keep freezing.
How to analysis toxicologic? It means all materials used for collection or handing should be made of plastic and free of contaminating trace elements
What is somatic gene analysis for?
Detection of mutation. The tissues are usually formalin-fixed and paraffin-embedded (FFPE). The specimens in optimal cutting temperature (OCT) compound- mixture of polyvinyl alcohol and polyethylene glycol.
The method of testing hair and nails
They are used currently limited genomic identification, and also used for drug and trace metal analysis but poor standardization of assays
What are procedures of specimens for analysis?
Identification, preservation, separation and storage, and transport.
How to maintenance of specimen identification?
All specimens treated as if infectious; no special labeling. They need for adequate labeling, regardless of size or treatment of container.
Preservation of specimens are Proper container and labeling, careful transportTemperature constraintsSeparation of serum and plasma, hemolysisChallenges of RNA recoveryRemote facilities.
Separation of plasma and serum:
- As soon as possible but not prematurely- Room temperature storage if centrifugation not
possible in normal window Freezer or cold storage after centrifugation
Centrifugation with a stopper in place:
- Prevents evaporation or aerosolization- Absolutely necessary for volatiles- Maintains anaerobic conditions
pH changes induced by removal of stopper before
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Chem PPT Flashcards, Unit 1
centrifugationCryopreservation: - Useful in preserving WBCs and DNA
- Preventing shearing of DNA Thorough mixing after thawing
Requirements for referring specimens to a CAP accredited referral laboratory:
For CAP accredited laboratories, it is a requirement that the referring laboratory validate that the referral laboratory is CLIA certified before specimens are shipped.
Controllable Pre-analytical variables include:
- Physiological Variables Posture Exercise and Physical training Circadian variation Menstrual cycle
Travel Diet Food ingestion Vegetarianism Malnutrition Fasting and Starvation Lifestyle
Smoking Alcohol
Drug Administration Prescribed medication Recreational drug ingestion
Herbal preparationsUncontrollable Pre-analytical variables include:
Biological influences Age Sex Race
Environmental factors Altitude Ambient temperature Geographical location of residence Seasonal influences
Underlying medical conditions Obesity Blindness Pregnancy Stress Fever Shock and trauma
Transfusion and InfusionWhat are effects of changes in posture:
- Changes in posture result to hydrostatic efflux of water and filterable substances from the intravascular space to the dependent interstitial fluid of the extracellular space
Increase in potassium (0.2-0.3 mmol/L) occurs after an
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Chem PPT Flashcards, Unit 1
individual stands for 30 minutesWhat type of physical variation causes Shifts of fluid between intravascular and interstitial compartments?
Exercise and Physical Training
Name one of the variations can cause Changes in hormone concentration in analyte?
Exercise and Physical Training
Loss of fluid due to sweating can be due to what type of variables?
Exercise and Physical Training
What does Circadian Variation refer to?
The pattern of production, excretion and concentration of analytes each 24 hours
What factors contributes to Circadian Variation?
posture, activity, food ingestion, stress, daylight or darkness and sleep or wakefulness
Give some examples of Circadian Variation?
Cortisol and Iron higher at 8AM and lower at 4PMPotassium higher in AM than PM
Why Menstrual Cycle is considered one of the preanalytical controllable variable?
Because the concentrations of plasma female sex hormones and other hormones are affected by the menstrual cycle.
How does Travel across several time zones affect the normal circadian rhythm?
Due to altered pituitary and adrenal functions
How many days is required to establish a new stable diurnal rhythm after travel across 10 time zones?
Five (5) days
How does Synthetic diets affect the amount of protein in the plasma?
Day to day changes
Which plasma constituents will be increased when Diet mainly consists of starch or sucrose?
ALP and LD
Which plasma constituents will be reduced when sucrose intake is decreased?
Plasma triglyceride concentration
Which plasma constituents will be reduced in high carbohydrate diet?
the VLDL cholesterol concentration, triglycerides and protein
Individuals who eat many small meals throughout the day give…………….?
lower the VLDL cholesterol concentration, triglycerides and protein
How food ingestion is affected the concentration of certain plasma constituents?
With the time between ingestion of a meal and collection of blood.
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What plasma constituent are reduced in individuals who have been vegetarians for a long time?
LDL cholesterol, total lipids, and phospholipids
Does Vegetarianism affect both HDL and LDL cholesterol concentrations?
Yes, In strict vegetarians, the LDL concentration may be 37% less and the HDL cholesterol concentration 12% less done in nonvegetarians
What are some causes of malnutrition?
Malnutrition causes reduction of total serum protein, albumin, beta globulin, complement C3, retinol binding globulin, transferrin, and prealbumin
In a fasting/starving state, what occurs to the concentration of glucose?
Glucose concentration decreases by as much as 18 mg/dL
In a fasting/starving state, what occurs to the secretion of insulin and glucagon?
Insulin secretion is greatly reduced whereas glucagon secretion may double
What is stimulated by a fasting/starving state?
Lipolysis and hepatic ketogenesis our stimulated
In a fasting/starving state, what does the body use for energy?
Keto acids and fatty acids become the principal sources of energy for muscle
What is the impact of nicotine on the body?
Nicotine increases the concentration of epinephrine in the plasma and the urinary excretion of catecholamines and their metabolites
Does smoking increase or decrease glucose concentrations?
Glucose concentration increases by 10 mg/dL within 10 minutes of smoking a cigarette
Does smoking increase or decrease plasma growth hormone concentrations?
Plasma growth hormone concentration may increase tenfold within 30 minutes
How are immunoglobulins affected with smoking?
IgA, IgG, and IgM levels are generally lower in smokers, whereas IgE concentration is higher
How does smoking affect sperm count and activity?
Sperm count of male smokers is reduced compared to non-smokers; number of abnormal forms is greater and sperm motility is less
How does alcohol ingestion affect blood glucose concentrations?
It increases blood glucose concentration by 20 to 50%
What is used as a marker of persistent drinking?
Increased activity of gamma glutamyltransferase (GGT) enzyme is often used as a marker of persistent drinking
What is chronic alcoholism associated with?
Chronic alcoholism is associated with abnormal pituitary, adrenocortical, and medullary function
How can intramuscular drugs alter blood serum?
Drugs administered intramuscularly can cause increased amounts of CK and LD into the serum.
What is recreational drug ingestion?
It refers to the ingestion of compounds for mood-altering purposes.
What are some examples of recreational drugs and their side-effects on the body?
Amphetamines increase the concentration of free fatty acids, morphine increases the activity of amylase, lipase, ALT, AST, ALP and serum bilirubin, and cannabis increases plasma concentrations of
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Chem PPT Flashcards, Unit 1
sodium, potassium, urea, chloride and insulin but decreases those of creatinine, glucose and uric acid
What types of herbs can cause hematuria and albuminuria over time?
Long-term use of aloe vera, sandalwood, cascara sagrda may cause hematuria and albuminuria.
Green tea has been reported to cause what?
Microcytic anemia
What are tonka beans known to cause?
Reversible liver damage
What is an uncontrollable variable?
Age; Newborn, the older child to puberty, the sexually mature adult, and the elderly adult
What does age have a notable effect on?
Age has a notable effect on reference intervals particularly hormones
What sort of changes are usually seen after puberty between young female and male humans?
Characteristic
What type of hormones, such as prolactin, become apparent?
Sex hormones
Certain biological characteristics, such as greater muscle mass in men, can produce what type of differences in men and women?
Higher enzyme readings
After menopause, activity of what enzyme increases in women until it is higher than in men?
ALP
Is total serum protein concentration known to be higher in people that are black or white?
Black
Is serum albumin typically less in people that are black or white?
Black
In_____ men, serum IgG is 40% higher, and serum IgA may be 20% higher than in ____ men
Black, white
One type of environmental factor?
Altitude
Why is it that in individuals living at a high altitude, blood hemoglobin and hematocrit are greatly increased?
because of reduced atmospheric PO2.
The fasting basal concentration Growth hormone
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Chem PPT Flashcards, Unit 1
of ______ is high in individuals living at the high altitude, but concentrations of renin and aldosterone are decreased.What takes longer? Complete adaption to higher or lower altitudes?
Higher
What can ambient temperature have an effect on?
Body fluids
Acute exposure to heat may decrease plasma protein concentration by up to what percent?
10%
When you sweat, what is being lost?
Salt and water
Ambient temperature may cause a decrease in plasma potassium by as much as what percent?
10%
What can you expect to see an increase in serum concentrations of in people who live in areas with hard water?
Cholesterol, triglycerides, and magnesium
In areas where there is much heavier automobile traffic, what can you expect to see an increase in?
Carboxy hemoglobin
Individuals who work indoors, as opposed to those who work outdoors, will likely have a higher concentration of what?
Vitamin D
Serum concentration of cholesterol, triglycerides and beta lipoproteins are positively correlated with what underlying medical condition?
Obesity
Serum LD activity and glucose concentration increase in both sexes with an increase of what?
Weight
In men, with increasing body weight, what else can you expect to see an increase in?
Serum AST, creatinine, total protein and blood hemoglobin concentration
In women, with increasing body weight, what else can you expect to see an increase in?
Serum calcium
Normal stimulation of what The hypothalamic pituitary axis
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Chem PPT Flashcards, Unit 1
body part is reduced with blindness?In people with blindness, The normal diurnal variation of what hormone may or may not persist?
Cortisol
As a result of reduced aldosterone secretion, plasma levels of what compounds are also reduced?
Sodium and chloride
In individuals with blindness, plasma glucose may be _____ and insulin tolerance is ____.
Reduced, less
During pregnancy, what type of lipids can you see an increase in?
Cholesterol, triglycerides
Urine volume ___ during pregnancy
Increases
The glomerular filtration rate increases by what percent during the third trimester.
50%
The erythrocyte sedimentation rate increases by what fold during pregnancy.
Fivefold
What types of stress can influence concentration of plasma constituents?
Physical and mental stress.
What plasma constituents can anxiety stimulate increased secretion?
aldosterone, angiotensin, catecholamines, cortisol prolactin renin somatotropin, TSH Vasopressin Albumin Cholesterol Fibrinogen Glucose Insulin lactate.
What is reduced in secretion during fever?
T4
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Chem PPT Flashcards, Unit 1
Which hormones are increased in excretion during fever?
free cortisol 17-hydroxycorticosteroids
17-ketosteroidsDuring shock and trauma, what stimulates increase in serum cortisol concentration, and by how much?
Corticotropin secretion is stimulated to produce a threefold to fivefold increase in the serum cortisol concentration
During shock and trauma, what increases excretion and secretion, respectively?
17-hydroxycorticosteroid and catecholamines
Which activities are increased during shock and trauma?
Aldosterone and renin activity are increased
What is increased and decreased during transfusions of whole blood or plasma?
Transfusion of whole blood or plasma raises the plasma protein concentration.
Serum LD activity, primarily LD-1 and LD-2 isoenzymes, and bilirubin are increased.
Transfusions may reduce levels of sodium chloride and water retention but may increase potassium concentration.
What is a delta check and what is it used for?
It is the difference between two successive results, regardless of interval between, and it is used to identify a clinically significant change in values.
What is the reference change value?
The reference change value is the value that must be exceeded before a change in consecutive test results is statistically significant.
Which population is the reference change value generally higher?
The reference change value is generally higher in hospitalized people than in healthy ones
What are other terms for Total Quality Management (TQM)?
Total Quality Control Total Quality Leadership Continuous Quality Improvement Quality Management Science Industrial Quality Management.
When implementing TQM, the framework for quality management emphasizes establishment of:
1. Quality Laboratory Processes (QLPs)2. Quality Control (QC)3. Quality Assessment (QA)4. Quality Systems (QSs)
What is Quality Laboratory Processes (QLPs)?
QLPs include analytical processes, general policies, practices, and procedures that define how all aspects of the work are done.
What is Implementing TQM? Completion of Total Quality Management, for example, QLP, QC,
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Chem PPT Flashcards, Unit 1
QA, QI, QP.What is QC? Quality Control emphasizes statistical control procedures but also
includes non-statistical check procedures such as linearity checks, reagent and standard checks, and temperature monitors.
What is QA? Quality Assessment concerned primarily with broader measures and monitors of laboratory performance such as turnaround time, specimen identification, patient identification, and test utility.
What is Turnaround Time (TAT)?
The time between when a test is orders or a specimen is submitted for analysis and when the test results are reported.
What is QI? Quality Improvement provides a mechanism through which one can act on those measures.
What is QP? Quality Planning provides the planning step.What is Total Quality Management?
Is considered a quality system that is implemented to ensure quality.
It is a set of key quality elements that must be in place for other organization's work operations to function in a manner to meet the organization's stated quality objectives.
What is QS Quality System include the following: Documents and records Organization Personnel Equipment Purchasing and Inventory Process control Information and Occurrence Management Assessment: external and internal Process Improvement3. Customer service
What is Personnel Competency and Training?
Importance of people, training, and education A key factor for successful training and assessment of
laboratory staff is the planning and implementation of targeted education programs.
Assessment of competence in job tasks as required by CLIA must be conducted semiannually the first year of employment and annually thereafter, and upon implementation of new test methodology before reporting of patient test results.
Detailed directions on how to develop and implement a training and competency assessment program that meets regulatory requirements, and provides example of forms for documentation and record keeping should be made available.
Design of an in-service training program. Internet education programs provide an effective, cost-
efficient way to implement in-service training.Web-based training programs in quality control concepts are
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Chem PPT Flashcards, Unit 1
available.How many phases are presence in a clinical testing process?
Phases of total testing process: 1. Pre-analytical (Pre-Examination) 2. Analytical (Examination) 3. Post analytical (Post-Examination)
What method is considered in analytical method?
Components of a reliable analytical method has to be considered
What should be monitored in a laboratory-wide basis?
Variables should be monitored on a laboratory-wide basis
What are the documentation of analytical protocols?
Documentation of analytical protocolsa) Procedure documentb) Laboratory manual
What are the procedures involved in monitoring of technical competency?
Monitoring of technical competencya) Written list of objectivesb) Incident reports, internal and external QC
checksc) In-service and continuing education
Employee conferences to detect nontechnical issuesWhat are the Statistical control of analytical methods?
Statistical control of analytical methodsa) Comparison of observed and known valuesb) Use of control limits to detect problemsc) Need for control materialsd) Selection of control productse) Use of control chartsf) Calculation of control limitsg) Interpretation of control datah) Reducing the risk of false alarmsi) Levey-Jennings chartj) Westgard multirule procedurek) Identifying sources of analytical errors
Combined use of liquid controls and moving averages of patient values for quality control monitoring
What does the unit identify? The unit identifies the dimension - mass, volume, or concentration - of a measured property
What does the number indicate?
The number indicates how many units are contained in the property
How is reagent-grade water prepared?
It’s prepared by distillation through the process of vaporizing and condensing liquid to purify or concentrate a substance.
What is ion exchange? The process that removes ions to produce mineral free deionized water.
What is the process of reverse osmosis?
Water is forced through a semipermeable membrane that acts as a molecular filter.
How effective is reverse osmosis?
It removes 95-99% of organic compounds and bacteria; 90-97% of all ionized and dissolved minerals.
Why do we us ultraviolet oxidation?
Using ultraviolet radiation eliminates many bacteria and cleaves many ionizing organics.
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Chem PPT Flashcards, Unit 1
Whose specifications must reagent grade or analytical reagent grade chemicals meet?
American Chemical Society (ACS).
What are ultrapure reagents? Reagents that exceed purity specifications ex. “spectrograde”, “nanograde”, “HPLC pure”.
What are reference materials? Any material or substance, one or more physical or chemical properties of which are sufficiently well established for it to be used for calibration of instruments, validation of methods, assignment of values to materials, and evaluation of the comparability of results.
What are primary reference materials?
Highly purified chemicals that are directly weighed or measured to produce a solution whose concentration is exactly known, 99.98% purity.
What are secondary reference materials?
Solutions whose concentrations cannot be prepared by weighing the solute and dissolving a known amount into a volume of solution.
Where are standard reference materials (SRMs) available?
NIST for clinical and molecular laboratories. Examples are pure crystalline standards, human-based standards, animal blood standards, standards containing drugs of abuse in urine and human hair, and SRMs used for DNA profiling/crime scene investigations.
Where are certified reference materials (CRMs) available?
At the Institute for Reference Materials and Measurements (IRRM) for clinical and molecular laboratories.
What glassware should be used for accurate work?
Only class A glassware
What are pipettes used for? They are used for the transfer of a volume of liquid from one container to another.
What are two kinds of pipettes? 1) To contain (TC) a specific volume of liquid2) To deliver (TD) a specific volume
What does a transfer pipette consist of?
Consist of a cylindrical bulb joined at both ends to a narrower glass tubing.
What are some characteristics of a transfer pipette?
A calibration mark is etched around the upper suction tube, and the lower delivery tube is drawn out to a gradual taper.
What are 2 types of transfer pipettes?
1) Volumetric transfer pipette2) Ostwald-Folin pipette
What is a volumetric transfer pipette used for?
Calibrated to deliver (TD) accurately a fixed volume of a dilute aqueous solution.
What is an Ostwald-Folin pipette used for?
Used for accurate measurement of viscous fluids, such as blood or serum.
What are some characteristics of the Ostwald-Folin pipette?
1) The bulb is closer to the delivery tip2) Has an etched ring near the mouthpiece indicating that it is a blow-out pipette.
What do measuring or graduated pipettes look like?
A piece of glass tubing that is drawn out to a tip, and is graduated uniformly along its length.
What are measuring or graduated pipettes used for?
Principally used for the measurement of reagents and generally are not considered sufficiently accurate for
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Chem PPT Flashcards, Unit 1
measuring samples and calibrators.What are 2 measuring or graduated pipettes?
1) Serological Pipette2) Mohr Pipette
How does a Serological pipette look like?
1) Has graduation marks down to the tip, visible or not visible2) Must be blown out to deliver the entire volume of the pipette3) Has an etched ring near the bulb end of the pipette signifying that it is a blowout pipette
How does a Mohr pipette look like?
It is calibrated between two marks.
What are some pipetting techniques?
1) Pipetting bulbs should always be used2) Pipettes must be held in the vertical position when the liquid level is adjusted to the calibration line and during delivery3) When sighted at eye level, use lower meniscus for readings4) Flow of liquid should be unrestricted, and the tapes should be touching the inclined surface of the receiving container.5) The pipette is allowed to drain, and then the remaining liquid is blown out with a pipetting bulb
What is a micropipettes ? A hallow glass tube used for measuring small volumes of liquid in microliters and transfer of liquid from one source to anothere
Pipettes come in different sizes?
Yes from single piece glass pipettes to more complex adjustable or electronic pipettes for various purposes with differing levels of accuracy and precision
What is the purpose of a pipette ?
To draw up liquid for the purpose of measuring and transferring a specific volume of liquid
What is the mouthpiece of the pipette?
The end of the pipette to which suction is applied to draw up liquid into the pipette
What is the calibration lines of a pipette?
Marks on the stem of the pipette to show the point where liquid must be drawn to give a specific volume
What is Volume of the pipette ? Stated in millimeters example inscription may read 10ml in 1/10 ml and the pipette is graduated in 1/10 ml increments allowing it to be used to measure volumes up to 10 ml
What is the T.D of the pipette? “To deliver “pipettes designed to deliver a specific volume of fluid
What is the T. C of the pipette “To contain “ pipettes designed to contain a certain volume of fluid
Why must a distinction between T.D and T.C pipettes be made ?
Because there may be a difference between the volume a pipette will contain and a volume it will deliver
What is T.D calibrated with ? Distilled or deionized waterWhat is T.C glassware calibrated with ?
Mercury
What is the meniscus ? A crescent shaped structure appearing at the surface of a liquid column it has the appearance of a contact lens
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Chem PPT Flashcards, Unit 1
What is centrifugation ? The process of using centrifugal force to separate the lighter portion of a solution mixture or suspension from heavier portions.
What is gravimetric ? The process used to measure the mass of a substanceWhat is a Double-pan, single-pan and electronic balances
Types of balances
Define Thermometry.Refers to the measurement of temperature to verify that devices measure within their prescribed temperature limits.
What are the two models of thermometers?
liquid-in-glass thermometer and thermistor probe
Define Dilution. decreasing the concentration or activity of a given solution by adding solvent
Define Evaporation. conversion of a liquid or volatile solid to vaporDefine Lyophilization. better known as freeze drying is used in laboratory medicine
for the preparation of calibrators, control materials, reagents, and individual specimens for analysis.
Define Filtration. passage of a liquid through a filter by means of gravity, pressure, or a vacuum
Which agencies and organizations address issues on safety?
-Occupational Safety and Health Administration (OSHA)-Centers for Disease Control and Prevention (CDC)-The Joint Commission (TJC)-College of American Pathologists (CAP)
What are the key elements to ensure safety in the clinical laboratory?
-A formal safety program-Documented policies and effective use of mandated plans and/or programs-Identification of significant occupational hazards such as biological, chemical, fire and electrical hazards
Who is the “Safety Officer” or “Chair of the Safety Committee?
The person who is given the responsibility to implement and maintain a safety program.
Who will provide technical guidance in the development of the chemical hygiene plan (CHP)?
-chemical hygiene officer
What are the safety standard for laboratory environments?
proper labeling of chemicals, types and locations of fire extinguishers, hoods that are in good working order, proper grounding of electrical equipment, ergonomic issues and means for the proper handling and disposal of biohazardous materials.
What does PPE stand for? Personal protective equipment.What are the primary requirements for PPE?
Clothing such as laboratory coats, gowns or scrubs, gloves and eye protection (face shields)
What are the safety equipments used in camical laboratory?
-Personal protective equipment (PPE)-Eye washers or face washers-Heat-resistant (non-asbestos) gloves
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Chem PPT Flashcards, Unit 1
-Eye safety devices such as safety goggles, glasses and visors-Desiccator guards-Chemical fume hood
What does OSHA stand for? Occupational Safety and Health AdministrationWhat does CMC stand for? Center for Medicare and Medicaid ServicesWhich agencies used for safety inspection?
-Occupational Safety and Health Administration (OSHA)-Commission on Inspection and Accreditation of the CAP-The Joint Commission (TJC)-Center for Medicare and Medicaid Services (CMS)
What does MSDS stand for? Material Safety Data SheetHow to used MSDS in chemical hygine plan?
The need for Material Safety Data Sheet (MSDS) which defines each chemical is toxic, carcinogenic or dangerous
How to used Exposure control plan?
Ensures the protection of laboratory workers against potential exposure to blood-borne pathogens and ensures that the medical wastes produced by the laboratory are managed and handled in a safe and effective manner.
How to used Tuberculosis control plan?
Prevent the transmission of tuberculosis by early identification and isolation of patients at risk, environmental controls, appropriate use of respiratory protection equipment, education of laboratory employees and early initiation of therapy.
How to work Ergonomics program?
Designed to prevent work-related musculoskeletal disorders through prevention and engineering controls
What type of hazards encountered in the laboratory?
-Biological-Chemical-Electrical-Fire hazards
What is the principle of the Universal Precautions?
To treat all human blood and other potentially infectious materials as infectious
The purpose of barrier protection and other Personal Protection Equipment is to?
prevent the skin and mucous membrane contamination from specimens
Proper storage and use of chemicals is necessary to prevent dangers such as:
Burns, explosions, fires and toxic fumes
What is the proper way of diluting acids?
By slowly adding them to water while mixing
How should hazardous chemicals be dispensed?
With a commercially available automatic dispensing device
To avoid chemical hazards, how should organic solvents be handled?
Under a fume hood
List all the ways electrical hazards can be prevented in the lab:
Prohibit use of all extension cords Worn wires on all electrical equipment should be
replaced immediatelyAll equipment should be grounded with the use of three-prong plugs
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Chem PPT Flashcards, Unit 1
Class A fire is caused by? Ordinary CombustiblesClass B fire is caused by? Flammable liquids and gasesClass C fire is caused by? Electrical equipmentClass D fire is caused by? Powdered metal (combustible) materialClass E fire is classified as? A fire that cannot be extinguishedDefine Photometry -measurement of luminous intensity of light or amount of
luminous light falling on a surface from such a source -Uses filter to isolate a narrow wavelength range of the spectrum for measurements
Define Spectrophotometry -measurement of intensity of light at selected wavelengths-Use prisms or gratings to isolate a narrow wavelength range of the spectrum for measurements
What is Photometric measurement ?
The process use to measure light intensity independent of wavelength
What is wavelength? A characteristic of electromagnetic radiation; the distance between two wave crests that is measured in nanometers (nm)
What does Beer’s Law state? The concentration of a substance is directly proportional to the amount of light absorbed or is inversely proportional to the logarithm of the transmitted light.
What is a tungsten light bulb? A light source in the visible range of spectra. An example is a quartz halogen lamp.
What is the function of a mercury vapor lamp
Supplies the needed energy in the UV region. It is used forcalibration purposes but is not practical for absorbancemeasurements because it is used only at certain wavelengths
Name the 10 parts that are in a Single-beam spectrophotometer.
Manual operation procedure Types of light sources Filters Monochromators Fiber optics Cuvets Photodetectors Readout devices Digital hardware and softwareRecorders
Name the 2 types of Light source.
• Incandescent and laser
Name the 3 types of Filters. • Glass, Prisms, GratingsSpectrophotometers are classified as a
• Single- or Double-beam
What are the 2 choices of monochromators.
• Bandwidth and Turbidity
What does a cuvet do? • Absorbs a portion of radiant energy.
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Chem PPT Flashcards, Unit 1
What does a photodetector do? • Converts light into an electrical signal that is proportional to the number of photons.
Name the 4 Performance parameters of an instrument.
Comparison of unknown with calibrator(s) Comparison with published/previously determined values NIST-provided SRMS for comparison• IRMM-provided reference materials
What does NIST stand for? • National Institute if Standards and TechnologyWhat does SRMS stand for? • Standard Reference MaterialsWhat does IRMM stand for? • Institute for Reference Material and MeasurementsWhat is reflectance photometry?
• A spectrophotometric technique in which diffused light illuminates a reaction mixture in a carrier
What transformation/equation is used for converting data into a linear format in reflectance photometry
• Kubelka-Munk equation or Clapper-Williams transformation
What is used in dry film chemistry systems?
• Reflectance photometry
What is Atomic Absorption spectrophotometry?
• An optical technique in which an element in the sample is excited and the radiant energy produced is measured.
What are the 2 limitations of atomic absorption spectrophotometry?
Spectral interferences• Non-spectral interferences
What is another name for flameless method in atomic absorption spectrophotometry?
• Zeeman correction
Name the 7 components of an Atomic Absorption spectrophotometry.
Hollow cathode Chopper Flame Entrance Slit Monochromator Exit Slit• Detector
What is Fluorometry? Measurement of emitted fluorescent light
When does Fluorescence occur?
Fluorescence occurs when a molecule absorbs light at one wavelength and re-emits light at a longer wavelength.
What is an atom or molecule that fluoresces called?
A fluorophore
What is the best way to describe Flow Cytometry?
The process in which measurement of physical and/or chemical characteristics of cells or particles are made, while cells or particles pass, preferably in single file, through the measuring apparatus in a fluid stream.
Flow Cytometry is:a. Able to measure
multiple parameters including cell size,
D
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Chem PPT Flashcards, Unit 1
granularity, DNA and RNA content, DNA nucleotide ratios, chromatin structure, antigens, total protein content, cell receptor, membrane potential and calcium ion concentration.
b. It combines laser-induced fluorometry and particle light scattering analysis
c. Is the process in which measurement of physical and/or chemical characteristics of cells or particles are made, while cells or particles pass, preferably in single file, through the measuring apparatus in a fluid stream.
All of the above.What is a single-channel front surface photofluorometer dedicated to the analyses of zinc protoporphyrin in whole blood called?
Hematofluorometer
How does Phosphorescence differ from fluorescence ?
Phosphorescence continues even after radiation causing it has ceased.
What is Phosphorimetry ? Measurement of phosphorescence, a type of luminescence produce by certain substances after radiant energy or other types of energy are absorbed, with a longer decay time of emission.
Luminometry is all of these except:
a. Chemiluminescence, bioluminescence, electrochemiluminescence Are types of luminescence in which the excitation event is
B
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Chem PPT Flashcards, Unit 1
caused by a chemical, biochemical or electrochemical reaction, and not by photo illumination.
b. It has longer decay time of emission
c. Instruments for measuring this type of light emission are generally known as luminometers.
Nephelometry and Turbidimetry are:
Analytical techniques of measuring scattered light
Factors influencing light scatter include:
a. Effect of particle sizeb. wavelength dependencec. concentration of the
particlesd. distance of observatione. All of the above.
E
What are the 5 types of electrochemistry used in the clinical laboratory?
Potentiometry Voltammetry Amperometry Conductometry
CoulometryWhich electrochemical technique measures the difference in electrical potential between two electrodes (half-cells) in an electrochemical cell?
Potentiometry
What are the three types of potentiometric electrodes?
Redox electrodes Ion-selective membrane electrodes (glass and polymer)
PCO2 glass-sensing electrodes
Potentiometry is usually applied for?
pH monitoring Electrolyte determination (ISE)
Electrodes for PCO2What is Voltammetry? An electrolytic electrochemical process in which a specific oxidation or
reduction reaction occurs at the surface of the working electrode.What process in voltammetry provides the analytical information required?
The charge transfer (current flow) at the surface of the working electrode.
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Chem PPT Flashcards, Unit 1
Name 2 applications in which voltammetry is used?
Anodic stripping voltammetryRapid scan cyclic voltammetry
What method of voltammetry is used to quantify dopamine in brain tissue of freely moving animals?
Rapid scan cyclic voltammetry
What method of voltammetry is used for detecting trace concentrations of toxic metal ions?
Anodic stripping voltammetry
Which electrochemical process monitors current at the fixed (controlled) voltage between working and reference electrodes in an electrochemical cell?
Amperometry
Amperometry is applied for? Clark amperometric PO2
Conductometry is used in order to determine what?
The quantity of an analyte present in a mixture; by measuring its effect on the electrical conductivity of the mixture.
Name 2 purposes for which conductometry is used?
Conductivity-based hematocrit measurementsCoulter principle - electronic counting of blood cells
An electrochemical technique that measures the electrical charge passing between two electrodes in an electrochemical cell, with the amount of charge passing between the electrodes being directly proportional to oxidation or reduction of an electroactive substance at one of the electrodes is called____________.
Coulometry
Coulometry is applied in _________
Coulometric titration of chloride
An optical sensor used in analytical instruments to measure pH, blood gases and electrolytes
Optodes
What specific type of chemical sensor that consist of a biological recognition element and physicochemical transducer, and often an electrochemical or optical device?
Biosensors
What special class of Affinity sensors
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Chem PPT Flashcards, Unit 1
biosensors in which the immobilized biological recognition element is a binding protein?The migration of charge solutes or particles within a liquid medium under the influence of an electric field.
Electrophoresis
What is Isoelectric point (pl)
The pH at which a molecule has no net charge and will not migrate during electrophoresis
An ampholyte is _____________
A molecule that is positively or negatively charge on the basis of the pH of the solution in which it resides;
What molecule behaves as an ampholyte in a solution and are considered amphoteric? It also contains many ionizable amino and carboxyl groups.
Protein
A measuring technique that uses an optical system to scan and quantify electrophoretic fractions separated on the gel or other medium.
Densitometry
In electrophoresis, after the support is removed from the electrophoresis cell, dried and fixed to prevent diffusion of sample components, it is then ________ in order to visualize the individual protein zones.
Stained
An electrophoresis technique that produces zones of proteins, which are heterogeneous and physically separated from one another.
Zone electrophoresis
What are the factors affecting electrophoresis?
The net electrical charge of the molecule The size and shape of the molecule Electric field strength Properties of the supporting medium
Temperature of operationAccording to the theory of electrophoresis, anions move through the solutions toward the______.
Anode
According to the theory of electrophoresis, cations move
Cathode
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Chem PPT Flashcards, Unit 1
through the solutions toward the __________.A cathode is a________ electrode. Choose one only.
a. Negativeb. Positivec. Polarizedd. Neutral
A Negative
A anode contains delivers a continuous _______ charge to the solution. Select one option.
a. Negativeb. Positivec. Polard. Bipolar
B Positive
A new MLT lab requires a new power supply for electrophoresis procedures. Select the correct one from the catalog below:
a. Trans-ductor Pulse Generator
b. Inductive Power Supplyc. Isolectric Focusing
Power Supplyd. Car Battery
C. Isolectric Focusing Power Supply
The buffer establishes the pH at which electrophoresis is performed.
Does it impact the solute as well? (Yes or No)
Yes
Evaluate the statement (True or False) Trans-barbital and barbital buffers have identical pH.
False
Which gels are compatible with electrophoresis? Choose 3 out of 5.a. SBA gelb. Triptic Soy Agarose Gelc. Starch gel and cellulose
acetated. Agarose gele. Polyacrylamide gel
C,D,E
If mobile phase is a liquid, the technique is
c. liquid chromatography
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Chem PPT Flashcards, Unit 1
called_____________a. Spectrum
Chromatographyb. Reverse Phase-Flow
Cytometryc. Liquid chromatographyd. Acid Reduction
ChromatographyIf mobile phase is a gas, the technique is called_____________
a. Spectrum Chromatography
b. Reverse Phase-Flow Cytometry
c. Acid Reduction Chromatography
d. gas chromatography
d. gas chromatography
In Column Chromotagraphy the stationary phase may consist of a particle of pure ______or _______, or it may be coated onto or chemically bonded to support particles. Select the correct media.
a. Silicon dioxide, sapphire bonded glass
b. Silicon, polymerc. Agarose Gel, Thayers
McConkey Mediad. SBA agar, plastic
b. Silicon, polymer
Planar Chromotography has two options for media. Identify the correct two.
a. sheet of paper (paper chromatography)
b. solid surface (thin-layer chromatography [TLC])
c. Silicond. Polymer
a. sheet of paperb. solid surface
Chromatography is a physical process whereby the components (solutes/analytes) of a sample mixture are separated as a result of their
a. Stationary, mobile phases
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Chem PPT Flashcards, Unit 1
differential distribution between the ________ and _______ phases.
a. Stationary, mobile phases
b. Gas, Solid Phasesc. Plasma, Superfluidicd. Liquid, Stationary
What is Planar Chromatography?
• Paper Chromatography• The stationary phase consists of a layer of water or a
polar solvent coated onto the fibers of the sheet of paper
• Thin Layer Chromatography (TLC)The stationary phase is a thin layer of particles of a material such as silica gel that is spread uniformly on a glass plate or a plastic or aluminum sheet
What is the reference value in planar chromatography?
• Rf value• Expression of solute's migration in TLC or PC• the ratio of solute migration to solvent front migration
Distance from application pointto solute center
Rf = ------------------------------------------Distance from application point to mobile phase front
What is Gas chromotography? • Gas chromatography• A gas mobile phase, or carrier gas, is used to carry a
mixture of volatility solutes through a column containing the stationary phase, which usually is a nonvolatile liquid coated or bonded to particles or the inner surface of a capillary
• the mobile phase, or carrier gas, is typically an inert gas such as nitrogen, helium, or argon
• separation of analytes is based on differential partitioning into the stationary phase
What is Liquid Chromatography?
• Liquid chromatography• Separation is based on the differential distribution of
the solutes between a liquid mobile phase and a stationary phase
• When particles of small diameter are used as the stationary phase support, the technique is referred to as High Performance Liquid Chromatography (HPLC) or High Pressure Liquid Chromatography (HPLC)
What are the different chromatophric separation mechanisms?
• Ion exchange chromatography• Partition chromatography• Adsorption chromatography• Size exclusion chromatography
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Chem PPT Flashcards, Unit 1
• Affinity chromatographyWhat is ion exchange chromatography?
• Ion exchange chromatography• Based on exchange of ions between charged stationary
phase and ions of opposite charge in mobile phase• Cationic or anionic exchange resin
Used for the separation of amino acids, glycated hemoglobin, hemoglobin variants and oligonucleotides
What is partition Chromatography?
• Partition chromatography• Basis of separation is the differential distribution of
solutes between two immiscible liquids with one of the immiscible liquids serving as the stationary phase
• separation is based on differences in the relative solubility of solute molecules between stationary and mobile faces
• Classification of partition chromatography:1. Gas liquid chromatography (GLC)2. Liquid-liquid chromatography (LLC)
What is absorption chromatohraphy?
• Adsorption chromatography• The basis of separation is differential adsorption of
solutes on the surface of the stationary phase• Hydrogen bonding and hydrophobic interactions are the forces that mediate separations
What is size exclusion chromatography known as and what does it mean?
• Size exclusion chromatography• Also known as:• 1. Gel filtration chromatography• 2. Gel permeation chromatography• 3. Steric exclusion chromatography• 4. Molecular exclusion chromatography• 5. Molecular Sieve chromatography
• Basis of separation are the differences in their molecular sizes
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