Continued………

Seminar on

Presented bySudip Kumar C. modhPA/2010/11

SUDIP KUMAR

2

inorganic impurities are toxic at low levels, and these impurities should be monitored

to ensure safety

Sources of inorganic impurities include those that are deliberately added to the

process (e.g., catalysts),

undetected contaminants from starting materials or reagents

leaching from pipes and other equipment

from naturally derived plant or mineral sources

the level of each inorganic impurity should not exceed the limit defined in or

otherwise specified in the individual monograph.

Introduction

Why limit test????

SUDIP KUMAR

3ICH Q3A

Impurities in Drug Substances guidance, impurities are classifiedas organic, inorganic, and residual solvents

Classification of metal impurities…...

WHAT TO BE DISCUSSED………

Limit test of heavy metals

Limit test for Iron

Limit test of sulphated ash

Limit test for total ash

Total Organic Carbon

Limit test of N,N- Dimethylaniline

Limit Test for Fluorides

Cadmium, copper, iron, lead, nickel and zinc

Limit test for selenium

Limit Test for Magnesium

Limit test of arsenic and mercury

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SUDIP KUMAR

Limit test of heavy metals: ( 2.3.13.)IP (GENERAL NOTICES)

Tests with numerical limits and assays, quantity stated to be taken for testing is

approximate

amount actually used, which may deviate by not more than 10 per cent from that stated, is

accurately weighed or measured

result of analysis is calculated from this exact quantity..

In tests where the limit is not numerical but usually depends upon comparison with the

behaviour of a reference in the same conditions, the stated quantity is taken for testing.

Reagents are used in the prescribed amounts.

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SUDIP KUMAR

Limit test of heavy metals:IP ( 2.3.13.)

Limit for heavy metals is indicated in in terms of

ppm, i.e., the parts of lead, Pb, per million parts (by weight) of the substance under

examination

Lead Nitrate Stock Solution: 0.1598 g of lead nitrate in (100 ml of water +1 ml of nitric

acid) dilute to 1000 ml with water

Lead Standard Solution:

Dilute 10 ml of lead nitrate stock solution with water to

100 ml

Each mL of Standard Lead Solution contains ≡ 10 µg of lead

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SUDIP KUMAR

Limit test of heavy metals:

USP <231>

metallic impurities tare colored by sulfide ion, under specified test conditions,

not exceed limit specified in the individual monograph as a

percentage (by weight) of lead in test substance

Determination by concomitant visual comparison with control (Standard Lead

Solution)#

Determine the amount of heavy metals by Method I, unless otherwise specified in

the individual monograph

.Types of methods Nature of substances

Method I that yield clear, colourless preparations

Method II do not yield under test conditions for Method I, or

form complex , interfere with precipitation by

sulfide ion, or for fixed and volatile oils

Method III wet-digestion method, when Method I nor Method

II can be used

#[note—Substances that typically will respond to this test are lead, mercury, bismuth, arsenic, antimony, tin, cadmium, silver,

copper, and molybdenum.]

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USP <231>

Monitor Preparation

Test Preparation +2.0 mL of Standard Lead Solution

Lead Nitrate Stock Solution

Standard Lead Solution as per IP

Limit test of heavy metals:

BP (Ph. Eur. method 2.4.8)

Lead Nitrate Stock Solution

Standard Lead Solution as per IP

Blank solution: 10 ml of water R and 2 ml of the test solution

Methods Developed By Thioacetamide Reagent R

Sodium Sulphide Solution R1 (0.1 Ml) as Alternative

If Sodium Sulphide Solution R1 Is Used Instead, To Be Include For Methods A And B

Monitor solution

Same quantity prescribed for the test + volume of lead standard solution prescribed

for preparation of the reference solution

Apparatus for limit test of heavy metals:

spots on the filters obtained with the different solutions

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SUDIP KUMAR

Limit test of heavy metals:

BP (Ph. Eur. method 2.4.8)

Apparatus for limit test of heavy metals

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IP BP USP

Method A

Standard solution:

Into a 50-ml Nessler cylinder

pipette 1.0 ml of lead std

solution (20 ppm Pb)dilute

with water to 25 ml

Adjust with dilute acetic acid

(1 N CH3COOH) or dilute

ammonia solution (10 per

cent w/w of NH3) to pH

between 3.0 and 4.0, dilute

with water to 35 ml and mix.

Method A

Reference solution

(standard) A mixture of 10

ml of lead standard solution

(1 ppm Pb or 2 ppm Pb) R,

as prescribed, and 2 ml of

prescribed aqueous solution

of substance to be examined

Method I

Standard Preparation

Into a 50-mL colour-

comparison tube

pipette 2 mL of Std Lead

Solution (20 µg of Pb), and

dilute with water to 25 ml

adjust with 1 N acetic acid or

6 N ammonium hydroxide to

a pH between 3.0 and 4.0,

dilute with water to 40 mL,

and mix

pH meter or short-range pH

indicator paper as external

indicator,

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SUDIP KUMAR

IP Method A BP Method A USP Method I

Test solution:

In 50-ml Nessler cylinder

place 25 ml of Solution for

test or dissolve specified

quantity of test substance in

sufficient water to produce

25 ml

Adjust with dilute acetic acid

or dilute ammonia solution to

a pH

between 3.0 and 4.0,

dilute with water to about 35

ml and mix

Test solution:

12 ml of the prescribed

aqueous solution of the

substance to be examined

Test Preparation:

In 50-mL color-comparison

tube, place 25 mL of the

solution prepared for the test

or, using the designated

volume of acid where

specified in the individual

monograph, dissolve in and

dilute with water to 25 mL*

pH is adjusted with 1 N

acetic acid or 6 N ammonium

hydroxide to a pH between

3.0 and 4.0,

dilute with water to 40mL,

and mix.

*g, of the substance to be tested, as calculated by the formula: 2.0/(1000L)

in which L is the Heavy metals limit, as a percentage.

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SUDIP KUMAR

IP Method A BP Method A USP Method I

Procedure;

To each of the cylinders

1 standard Solution

2 test solution

add 10 ml of freshly prepared

H2S solution, mix,

dilute to 50 ml with water,

allow to stand for 5 minutes

and view downwards over

white surface;

colour produced with the test

solution is not more intense

than that produced with the

standard solution

Procedure;

As per usp

Brown colour

Procedure:

To each of the three tubes

containing the

1 Standard Preparation

2 Test Preparation

3 Monitor Preparation

2 mL of pH 3.5 Acetate

Buffer,

then add 1.2 mL of

thioacetamide–glycerin base

TS,

Dilute with water to 50 mL,

wait for 2 minutes, and view

over white surface

colour of Test is not darker

than Standard

Monitor is equal to or darker

than Standard Preparation

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SUDIP KUMAR

IP BP USP

Method B

Standard solution:*

Test solution:

Test (crucible) +H2SO4 ignite at low temp

+ (2ml HNO3 + 5 drops H2SO4)

white fumes

Ignite,(muffle furnace)(500°-600°)to burnt off

carbon +4 ml HCl cover, digest(water-

bath) for 15 mins, uncover & evaporate , Moisten

with (1 drop H2SO4 +10 ml hot water)

digest for 2 min + NH4 solution

dropwise alkaline to litmus

paper

dilute to 25 ml & adjust pH between 3.0 and 4.0

by dilute CH3COOH ,Filter rinse crucible & filter

with 10 ml water, combine in 50-ml Nessler

cylinder, dilute to 35 ml and mix

Method B

Standard solution:*

Test solution:

As per method A

Method II

Standard Preparation*

Test Preparation:

Steam bath

ammonium hydroxide

40 ml

*process is same as method A /method I

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IP BP USP

Procedure*

Method C

Standard solution

Into a 50-ml Nessler cylinder

pipette 1.0 ml of lead

standard solution (20 ppm

Pb),

add 5 ml dilute

sodium hydroxide solution,

dilute with water to 50 ml

and mix

Procedure*

Method C

Standard solution

10 ml of the solution + add 2

ml of the test solution

Procedure*

Method III

Standard solution

*process is same as method A /method I

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USP Method III

Standard solution

Transfer(8 mL H2SO4+10 mL HNO3) clean, dry, 100-mL Kjeldahl flask

add more nitric acid = incremental volume of HNO3 added to Test Preparation

dense, white fumes

cool,add 10 mL of water;

if hydrogen peroxide was used in treating Test Preparation, add volume of 30% hydrogen

peroxide = that used for substance being tested. Boil dense, white fumes.

cool, +5 mL water, mix, boil dense, white fumes

Cool, dilute ,+ 2.0 mL of Standard Lead Solution (20 µg of Pb), and mix.

50-mL colour-comparison tube, rinse to volume is 25 mL, and mix

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SUDIP KUMAR

IP Method C BP Method C USP Method III

Test solution.

50-ml Nessler cylinder

place 25 ml test solution or

dissolve specified quantity of

substance

(20 ml H2O + 5 ml of dilute

NaOH)

Dilute to 50 ml

and mix.

Test solution.

Sample (silica crucible) with 4 ml

of 250 g/l solution of MgSO4 R

in H2SO4 R. Mix

white or at most greyish residue

≤ 800 °C

Moisten with dilute H2SO4R.

ignition < 2 h

5ml HCl + phenolphthalein

+conc NH3

pink colour

+ glacial acetic acid decolorized

+ 0.5 ml Filter & wash Dilute to

20 ml with water R.

Test solution:

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SUDIP KUMAR

USP Method III

Test Preparation: (wet-digestion method)

If solid substance—

weighed quantity 100-mL( Kjeldahl flask)at 45 angle

+ 8 mLH2SO4 and 10 mL of HNO3 to moisten it

boil

until solution darkens.

+2 mL HNO3

+ nitric acid (no darkening occurs) to dense, white fumes.

+ 5 mL water dense, white fumes & reduce volume

Add water examine colour of solution.

If color is yellow, +1 mL of 30 % hydrogen peroxide, dense, white fumes & volume of 2

to 3 mL.

still yellow, repeat 5 mL of water & peroxide treatment.

Cool, dilute cautiously with few mL of water, and rinse into a 50-mL colour-comparison tube,

volume shouldn‘t be exceed 25 mL.

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IP BP USP

Procedure.

similar to that of method A

Method D

Standard solution.

Into a small Nessler cylinder

pipette 10.0 ml of either lead

standard solution (1 ppm Pb)

or lead standard solution (2

ppm Pb)

Test solution.

Prepare as directed in the

individual monograph

and pipette 12 ml into a

small Nessler cylinder

.

Procedure.

similar to that of method A

Method D

Standard solution. As per

Method A(drying is done)

Monitor solution:As per

Method A(drying is done)

Test solution

As per method C

0.5 g of magnesium oxide

R1. is used instead of MgSO4

R in H2SO4 R

.

Procedure—

Similar to that of method I

USP contains only 3 methods

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IP BP USP

Procedure. Method D

standard solution+

2.0 ml of test solution

+2 ml of acetate buffer pH 3.5, mix,

+1.2 ml of thioacetamide reagent

2 mins

view downwards over white surface;

colour produced with test solution is

not more intense than that produced

with standard solution

Procedure. Method D

similar to that of method A

Method E

Test solution:

prescribed quantity of test

substance In 30 ml of water R

or prescribed volume.

Standard solution.

lead standard solution (1 ppm

Pb) R to the same volume as the

test solution

Procedure:

Apparatus for limit test of heavy

metals is used

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BP

Method F

Test solution:

As per USP Method III

Adjust pH 3.0-4.0 with conc NH3 R1 (dilute may be used) if desired, dilute

to 40 ml and mix.

+ 2 ml of buffer solution pH 3.5 R. Mix and add to 1.2 ml of thioacetamide reagent

Standard solution. Prepare at the same time and in the same manner as the test

solution, using the prescribed volume of lead standard solution (10 ppm Pb) R.

Monitor solution Prepare as described for the test solution, adding test substance to

lead standard solution (10 ppm Pb) R prescribed for the preparation of the reference

solution.

Blank solution Prepare as described for the test solution, omitting the substance to be

examined.

Dilute to 50 ml with water R and mix

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BP

Procedure. (Method F )

Examine vertically against white background.

brown colour in the test solution is not more intense than reference solution.

Test is in valid….

if reference solution does not show a brown colour compared blank solution or

if monitor solution is not at least as intense as the reference solution

Method G

(Based on high-pressure digestion method)

Test solution

Place test substance (not more than 0.5 g) in a suitable, clean beaker.

+ 2.7 ml H2SO4 R + 3.3 ml HNO3 R + 2.0 ml of strong H2O2 R using a magnetic stirrer.

Allow to react dry high-pressure-resistant digestion vessel (fluoropolymer or

quartz glass).

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SUDIP KUMAR

BP (Method G )

Standard solution.

Monitor solution as per method F

Blank solution

Procedure:

it includes use of both high-pressure-resistant digestion vessel and Apparatus for limit test of

heavy metals

Limit Test for Heavy Metals in Herbal Drugs and Fatty Oils

(Ph. Eur. method 2.4.27)

Examine by atomic absorption spectrometry (2.2.23)

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SUDIP KUMAR

Limit test for Iron

Principle:

Fe2+ React in an ammoniacal solution with thioglycollic acid

Pink to dip reddish purple coloured complex of iron Thioglycollate

Fe(SCH2COOH)2

Ferric ammonium sulphate ,FeNH4(SO4)2:12H2O,as standard

Stability of complex

Air oxidation

Thioglycollate reduce Fe3+ to Fe2+

20% citric acid to remove interference

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SUDIP KUMAR

IP BP USP

Iron Standard Solution (20 ppm Fe):

Dilute 1 ml 0.1726 % w/v solution of ferric

ammonium sulphate in 0.05 M H2SO4 to 10

volumes with water. Contains iron in ferric

state

Procedure.

Dissolve test or prepare as directed in

monograph, in Nessler cylinder. + 2 ml 20 %

w/v of iron-free citric acid + 0.1 ml of

thioglycollic acid, mix, make alkaline with iron-

free NH3 solution, dilute to 50 ml,

pink colour is not more intense than that of

2.0 ml of iron standard solution (20 ppm Fe)

in place of solution under examination

Same as IP

USP uses ammonium

thiocyanate

Limit test for Iron: 24

SUDIP KUMAR

IP Limit test of sulphated ash

2.3.18. Sulphated ash

Heat silica or platinum crucible to redness for 10 minutes

Cool(desiccator) weigh it

As per individual monograph, transfer to crucible 1 g of test substance under & weigh the

crucible

Ignite, to charring

Cool, moisten the residue with 1 ml of H2SO4, white fumes no longer evolved

and ignite at 800º ± 25º black particles disappeared.

Ignition without air currents.

+ drops of H2SO4 and heat

Repeat the operation until two successive

weightings do not differ by more than 0.5 mg.

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SUDIP KUMAR

EP Limit test of sulphated ash

Ignite a suitable crucible (silica or platinum )at 600° ± 50° C for 30 min,

allow to cool in a desiccator over silica gel and weigh.

Place in crucible and weigh. Moisten with 1 ml of H2SO4 ,

heat gently at as low temp until the sample is charred.

cool moisten with H2SO4 , heat gently until white fumes are no longer evolved

ignite at 600° ± 50° C until residue is completely incinerated

Ensure that flames are not produced at any time during the procedure.

Allow the crucible to cool over silica gel, weigh it again

If mass of the residue so obtained exceeds the prescribed limit, repeat the moistening with

H2SO4 and ignite to constant mass.

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SUDIP KUMAR

27

ICH guideline:

Q4B - ANNEX I

REGULATORY ACCEPTANCE OF ANALYTICAL PROCEDURES AND/OR

ACCEPTANCE CRITERIA (RAAPAC)

ON

RESIDUE ON IGNITION/SULPHATED ASH GENERAL CHAPTER

ANALYTICAL PROCEDURES AND/OR ACCEPTANCE CRITERIA (APAC)

Defination:

―The Residue on Ignition/ Sulphated Ash Test is a method to measure the amount of residual

substance not volatilized from a sample when the sample is ignited in the presence of

sulfuric acid, This test is usually used for determining the content of inorganic impurities in

an organic Substance.‖

Procedure given is similar to that of EP:

IP Limit test for total ash:

Total Ash

Method A. For crude vegetable drugs

2 to 3 g of air-dried drug in tarred platinum or silica dish and incinerate at a 450ºC

until free from carbon, cool and weigh

If carbon-free ash is not obtained, wash charred mass with hot water, collect residue on

filter paper, incinerate again until ash is white or nearly white

evaporate to dryness and ignite .

Calculate the percentage of ash on the dried drug basis

Method B. For all other substances

Heat, cool and weight platinum or silica crucible

weigh accurately about 1 g of test substance, Dry and ignite to constant weight in a muffle

furnace material should not catch fire at any time during procedure. If carbon-free ash

cannot be obtained proceed as directed in method A

Ignite to constant weight. Calculate the percentage of ash on the dried basis.

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IP Total Ash

Acid-insoluble ash

Use Method C unless otherwise directed.

Method C.

Boil ash (Method A or B) with 25 ml of 2M HCl

collect the insoluble matter in a Gooch crucible or on an ashless filter paper,

wash, ignite, cool in a desiccator and weigh.

Calculate % of acid-insoluble ash on the dried drug basis

Method D.

Place ash (Method A or B), or sulphated ash (2.3.18), as directed in the individual

monograph, in crucible, add 15 ml H2O + 10 ml HCl

Cover& boil & cool. Collect the insoluble matter on an ashless filter paper

wash to neutral, ignite to dull redness, cool in an a desiccator and weigh.

Calculate % of acid-insoluble ash on the dried basis.

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IP Total Ash

Water-soluble ash

Boil the ash (Method A or B) with 25 ml of water

collect insoluble matter in Gooch crucible or ashless filter paper

wash with hot water, and ignite (450ºC)

weight of the ash - weight of insoluble matter = weight of water-soluble ash

Calculate % of water-soluble ash on the dried basis

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SUDIP KUMAR

USP

<643> TOTAL ORGANIC CARBON

Total organic carbon (TOC) is an indirect measure of organic molecules present in

pharmaceutical waters

Two general approaches are used

TOC = TC – IC ( TOC=total organic carbon, TC=total carbon, IC=inorganic carbon )

TOC = POC + NPOC.(POC=purgeable organic carbon , NPOC= nonpurgeable organic carbon)

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SUDIP KUMAR

IP

N,N-DimethylanilineDetermine by gas chromatography (2.4.13).

Method AInternal standard solution. As per individual monograph or dissolve 50 mg of naphthalene in cyclohexane to produce 50 ml. Dilute 5 ml to 100.0 ml with cyclohexane

Test solution (a)

As per individual monograph or take 1.0 g of test substance to a centrifuge tube,

add 5 ml of 1M NaOH, +1.0 ml of cyclohexane,

shake centrifuge Use upper layer

Test solution (b)

As per individual monograph or take 1.0 g of test substance into a centrifuge tube + 5 ml of 1

M NaOH ,dissolve

add 1.0 ml of internal standard solution, shake and centrifuge

Use the upper layer

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SUDIP KUMAR

IP N,N-Dimethylaniline

Reference solution

Take 50.0 mg of N, N-dimethylaniline + 2 ml HCl and 20 ml H2O dissolve & dilute to 50.0 ml

Dilute 5.0 ml to 250.0 ml *

1.0 ml solution into a stoppered centrifuge tube add 5 ml of 1 M NaOH + 1.0 ml of the

internal standard solution

Stopper the tube and shake & Centrifuge if necessary and use the upper layer

Chromatographic system

– a glass column 2 m × 2 mm, packed with silanised diatomaceous support (125 to 180

mesh) impregnated with 3 per cent w/w polymethylphenylsiloxane,

– temperature: column.120º,

inlet port and detector. 150º,

– flow rate 30 ml per minute of nitrogen (carrier gas).

Inject 1 μl of each of the solutions.

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SUDIP KUMAR

IP N,N-Dimethylaniline

Method B

Internal standard solution.

dissolve 75 mg of N, N-diethylaniline in ( 2 ml HCl + 20 ml of water) dilute to 50 ml.

Dilute 2 ml to 100.0 ml with water.

Test solution (a)

Test solution (b) as per Method A

Reference solution.

as per Method A

*Dilute 2 ml to 100.0 ml with water

Chromatographic system

– a glass column 1.5 m × 4 mm, packed with 3 per cent w/ w of cyanoethyl-silicone gum (XE-

60 is suitable) on acid-washed silanised diatomaceous earth (80 to 100 mesh)

– temperature: column. 80º,

inlet port and detector. 150º

– flow rate 30 ml per minute of nitrogen (carrier gas)

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SUDIP KUMAR

IP N,N-Dimethylaniline

Procedure:

Record the chromatograms

and measure the areas for the major peaks

In chromatogram obtained with test solution (b) ratio of the

area of any peak due to N, N-dimethylaniline to area of the

peak due to the internal standard

is not greater than corresponding ratio in chromatogram obtained with internal standard

solution

USP <223>

1 method is given as per Method A of IP

Test solution as per IP Test solution (b)

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SUDIP KUMAR

BP:

Limit Test for Fluorides

(Ph. Eur. method 2.4.5)

Test solution:

With Prescribed qty, 0.1 g of acid-washed sand R and 20 ml of a mixture of equal volumes of

H2SO4 & H2O

Heat the jacket containing tetrachloroethane R maintained at its boiling point (146 °C)

distil, collect distillate in a 100 ml volumetric flask containing 0.3 ml of 0.1 M NaOH and 0.1

ml of phenolphthalein solution R

Maintain a constant volume (20 ml) in tube during distillation and ensure that the distillate

remains alkaline, adding 0.1 M NaOH if necessary.

Dilute the distillate to 100 ml with water R (test solution).

fluoride standard solution

5 ml of (10 ppm F) R instead of test substance

Procedure:

Into two glass-stoppered cylinders introduce 20 ml of test solution and 20 ml of the

standard and 5 ml of aminomethylalizarindiacetic acid reagent R

After 20 min, any blue colour in the test solution (originally red) is not more intense than

that in the standard

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Limit Test for Fluorides

As per BP: APPARATUS

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BPCADMIUM, COPPER, IRON, LEAD, NICKEL AND ZINC

Examine by atomic absorption spectrometry

Measure the content of cadmium, copper, iron, lead, nickel and zinc by the standard additions

method (2.2.23, Method II), using reference solutions of each heavy metal and the instrumental

parameters described in Table

Cd Ca Fe Ni Pb Zn

Wavelength nm 228.8 324.8 248.3 232 283.5 213.9

Slit width Nm 0.5 0.5 0.2 0.2 0.5 0.5

Lamp current mA 6 7 5 10 5 7

Ingition T ‗c 800 800 800 800 800 800

Atomisation T ‗c 1800 2300 2300

Back ground

corrector

On Off Off Off Off Off

Nitrogen flow l/min 3 3 3 3 3 3

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USP

Limit test for selenium

Stock Solution— is prepared by Dissolving 40.0 mg of metallic selenium in 100 mL of dilute

nitric acid

Standard Solution: prepared from Stock Solution

Test Solution:

100 to 200 mg, unless directed otherwise in the individual monograph

magnesium oxide is added for combustion and reduces soot formation

Procedure:

Is done in oxygen flask combustion and AAS

the absorbencies are compared of test and standard

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SUDIP KUMAR

BP

Limit Test for Magnesium

(Ph. Eur. method 2.4.6)

magnesium standard solution

1 ml of magnesium standard solution (10 ppm Mg) R and 9 ml of water R

Procedure:

Organic phase - of hydroxyquinoline R in chloroform R

aqueous phase used- butylamine R and triethanolamine R is added

For comparison aqueous phase used-

Any colour in the solution obtained from the substance to be examined is not more intense

than that in the standard.

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SUDIP KUMAR

BP: Limit test of ARSENIC AND MERCURY

Measure the content of arsenic and mercury in comparison with the reference solutions of arsenic or

mercury at a known concentration by direct calibration (2.2.23, Method I) using an automated

continuous-flow hydride vapour generation system.

absorbance of blank solution is automatically subtracted from value obtained with test solution

ARSENIC

Sample solution: 19.0 ml of the test solution or of the blank solution, add 1 ml of a 200 g/l solution of KI

A

Acid reagent Heavy metal-free hydrochloric acid R.

Reducing reagent A 6 g/l solution of sodium tetrahydroborate R in a 5 g/l solution of sodium

hydroxide R.

MERCURY

Sample solution Test solution or blank solution, as prescribed above.

Acid reagent A 515 g/l solution of heavy metal-free hydrochloric acid R.

Reducing reagent A 10 g/l solution of stannous chloride R in dilute heavy metal- free hydrochloric acid

Parameters are given in table

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SUDIP KUMAR

As Hg

Wavelength Nm 193.7 253.7

Slit width Nm 0.2 0.5

Lamp current mA 10 4

Acid reagent flow rate ml/min 1.0 1.0

Reducing reagent flow rate ml/min 1.0 1.0

Sample solution flow rate ml/min 7.0 7.0

Absorption cell Quartz Quartz

Background corrector off off

N2 flow rate l/min 0.1 0.1

Parameters are given in table (AAS)42

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SUDIP KUMAR

43

References:

Dr T. Narendra sir-- Inorganic Impurities in Drugs

Q4B - ANNEX I

Indian Pharmacopoeia 2007 Volume 1 page no,76-79

USP32–NF27

British pharmacopoeia Volume 4 2009

Dr T. Narendra sir-- Inorganic Impurities in Drugs

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Incredible India !!!!!

Thank u……….