(general principles and applications)

8/14/2019 (General Principles and Applications)

1/31


2/31

What is a Biosensor?


3/31

Biosensor Any device that uses specific biochemical reactionsthat uses specific biochemical reactions totodetect chemical compoundsdetect chemical compounds in biological samples .


4/31

Current DefinitionCurrent Definition

A sensor that integrates a biological element with a physiochemicaltransducer to produce an electronic signal proportional to a single

analyte which is then conveyed to a detector.


5/31

Components of aomponents of aBiosensoriosensor

Detecto


6/31

Father of the Biosensor

Professor Leland C Clark Jnr 19182005


7/31


8/31

1975 First commercial biosensor ( Yellow springsInstruments glucose biosensor)

1975 First microbe based biosensor, First immunosensor

1976 First bedside artificial pancreas (Miles)

1980 First fibre optic pH sensor for in vivo blood gases (Peterson)

1982 First fibre optic-based biosensor for glucose

1983 First surface plasmon resonance (SPR) immunosensor

1984 First mediated amperometric biosensor: ferrocene used with glucose oxidasefor glucose detection

History of Biosensors


9/31

1987Blood-glucose biosensor launched by MediSense ExacTech

1990SPR based biosensor by Pharmacia BIACore

1992Hand held blood biosensor by i-STAT

1996Launching of Glucocard

1998Blood glucose biosensor launch by LifeScan FastTake

1998Roche Diagnostics by Merger of Roche and Boehringer mannheim

Current Quantom dots, nanoparicles, nanowire, nanotube, etc

History of Biosensors


10/31

1. LINEARITY Linearity of the sensor should be highforthe detection of high substrate

concentration.2. SENSITIVITY Value of the electrode response per substrate concentration.

3 . SELECTIVITY Chemicals Interference must beminimised for obtaining the correctresult.

4. RESPONSE TIME Time necessary for having 95%of the response.

Basic Characteristics of aBiosensor


11/31

Biosensoiosenso

rAnalyte

Samplehandling/preparati

on

Detection

Signal

Analysis

Response


12/31

1. The Analyte ( What do you want to detect )

Molecule - Protein, toxin, peptide, vitamin, sugar,metal ion

2. Sample handling ( How to deliver the analyte to the sensitive region?)

(Micro) fluidics - Concentration increase/decrease),Filtration/selection

Biosensoiosenso

r


13/31

4. Signal4. Signal ((How do you know there was a detection)

3.3. Detection/Recognition

((How do you specifically recognize the analyte?)

Biosensoiosenso

r


14/31

Example of biosensorsxample of biosensors

Pregnancy test

Detects the hCG protein inurine.

Glucose monitoring device (for diabetes patie

Monitors the glucose level in the blood.


15/31

Example of biosensorsxample of biosensors

Infectous disease biosensor from RBS

Old time coal miners biosensor


16/31

Research Biosensorsesearch Biosensors

Biacore Biosensor platfor
http://images.google.se/imgres?imgurl=http://www.scieng.flinders.edu.au/images/faal/biacore.jpg&imgrefurl=http://www.scieng.flinders.edu.au/research/faal/instruments.html&h=643&w=852&sz=15&hl=no&start=14&sig2=yvN3tOeuYSTb7RZhWmeMiQ&um=1&tbnid=BPMGktcsbr648M:&tbnh=109&tbnw=145&ei=7rL7RqzNNqauwAH5j53lDw&prev=/images%3Fq%3Dbiacore%26svnum%3D10%26um%3D1%26hl%3Dnohttp://images.google.se/imgres?imgurl=http://www.scieng.flinders.edu.au/images/faal/biacore.jpg&imgrefurl=http://www.scieng.flinders.edu.au/research/faal/instruments.html&h=643&w=852&sz=15&hl=no&start=14&sig2=yvN3tOeuYSTb7RZhWmeMiQ&um=1&tbnid=BPMGktcsbr648M:&tbnh=109&tbnw=145&ei=7rL7RqzNNqauwAH5j53lDw&prev=/images%3Fq%3Dbiacore%26svnum%3D10%26um%3D1%26hl%3Dno


17/31

FluorescenceDNA Microarray

SPR Surface plasmon resonanceImpedance spectroscopySPM (Scanning probe microscopy, AFM,STM)QCM (Quartz crystal microbalance)SERS (Surface Enhanced Raman SpectroscopyElectrochemical

Typical Sensing Techniquesfor Biosensors


18/31

Types of Biosensorsypes of Biosensors

1. Calorimetric Biosensor

2. Potentiometric Biosensor 3. Amperometric Biosensor

4. Optical Biosensor

5. Piezo-electric Biosensor


19/31

Piezo-Electric BiosensorsPiezo-Electric Biosensors

The change in frequency is proportionalto the mass of absorbed material.

Piezo-electric devices use gold to detect thespecific angle at which electron waves areemitted when the substance is exposed to laser light or crystals, such as quartz, which vibrateunder the influence of an electric field.


20/31

Electrochemical BiosensorsElectrochemical Biosensors

For applied current: Movement of e- in redoxreactions detected when a potential is applied

between two electrodes.


21/31

PotentiometricBiosensor

For voltage: Change in distribution of charge is detected using ion-selective

electrodes, such as pH-meters.


22/31

Optical BiosensorsOptical Biosensors

Colorimetric for color Measure change in light adsorption

Photometric for light intensity

Photon output for a luminescent or fluorescent process can be detected

with photomultiplier tubes or

photodiode systems.


23/31

Calorimetric BiosensorsCalorimetric Biosensors

If the enzyme catalyzed reaction is exothermic,two thermistors may be used to

measure the difference in resistancebetween reactant and product and, hence,

the analyte concentration.


24/31

Electrochemical DNAElectrochemical DNABiosensor Biosensor

Steps involved in electrochemicalSteps involved in electrochemicalDNA hybridization biosensors:DNA hybridization biosensors:

Formation of the DNA recognition layer Formation of the DNA recognition layer

Actual hybridization eventActual hybridization event

Transformation of the hybridization eventTransformation of the hybridization event

into an electrical signalinto an electrical signal


25/31


26/31

Wearable Biosensors

Ring Sensor

Smart Shirt


27/31

Biosensors on theNanoscale

Molecular sheaths around the nanotube are developed thatrespond to a particular chemical and modulate the

nanotube's optical properties.

A layer of olfactory proteins on a nanoelectrode react withlow-concentration odorants (SPOT-NOSED Project).Doctors can use to diagnose diseases at earlier stages.

Nanosphere lithography (NSL) derived triangular Agnanoparticles are used to detect streptavidin down to onepicomolar concentrations.

The School of Biomedical Engineering has developed an anti-body based piezoelectric nanobiosensor to be used for anthrax,HIV hepatitis detection.


28/31

Potential Applicationsotential Applications

Clinical diagnostics Food and agricultural processes Environmental (air, soil, and water) monitoring

Detection of warfare agents.


29/31

Food AnalysisStudy of biomolecules and their interactionDrug DevelopmentCrime detectionMedical diagnosis (both clinical and laboratory use)(both clinical and laboratory use)Environmental field monitoringQuality control

Industrial Process ControlDetection systems for biological warfare agents

Manufacturing of pharmaceuticals and replacement

organs

Application of Biosensor


30/31

Biosensors play a part in theBiosensors play a part in thefieldfield of environmental quality,of environmental quality,medicine and industry mainlymedicine and industry mainlyby identifying material and theby identifying material and the

degree of concentrationdegree of concentrationpresentpresent


31/31

(general principles and applications)

Documents