Impurity of substance unit 1s

Impurities in Pharmaceutical
Substances
Department of Pharmaceutical chemistry/ By Mr. Pavan R. Badgujar
Impurities in Pharmaceutical
Substances
Department of Pharmaceutical chemistry/ By Mr. Pavan R. Badgujar

Points on Unit – I:
 History of Pharmacopoeia,
 Sources and types of impurities, Sources and types of impurities,
 Principle involved in the limit test for
 Chloride,
 Sulphate,
 Iron, Iron,
 Arsenic,
 Lead and Heavy metals, &
 Modified limit test for Chloride and Sulphate2
Modified limit test for Chloride and Sulphate 9/10/2018

HISTORY
INDIAN PHARMACOPOEIA
Department of Pharmaceutical Chemistry/ Mr. Pavan Badgujar
HISTORY
INDIAN PHARMACOPOEIA
Department of Pharmaceutical Chemistry/ Mr. Pavan Badgujar

• Impurities can have unwanted pharmacological
product quality and patient safety. Potential sources
What is Impurities..........?
product quality and patient safety. Potential sources
discussed for both drugs. The International Conference
a workable guideline regarding the control of impurities
• Impurities in pharmaceuticals are the unwanted• Impurities in pharmaceuticals are the unwanted
pharmaceutical ingredients (APIs), or develop during
formulated APIs to medicines. The presence of these
may influence the efficacy and safety of the pharmaceutical5
pharmacological or toxicological effects that seriously impact
sources and mechanisms of impurity formation are
What is Impurities..........?
sources and mechanisms of impurity formation are
Conference on Harmonization (ICH) has formulated
impurities.
unwanted chemicals that remain with the activeunwanted chemicals that remain with the active
during formulation, or upon aging of both API and
these unwanted chemicals even in small amounts
pharmaceutical products. 9/10/2018

• According to ICH, an impurity in a drug
of the new drug substance that is not the
substance”.
• There is an ever increasing interest in impurities• There is an ever increasing interest in impurities
purity profile but also impurity profile
regulatory requirements.
• The presence of the unwanted chemicals,
efficacy and safety of the pharmaceutical productsefficacy and safety of the pharmaceutical products
• “In the pharmaceutical world, an impurity
material, besides the drug substance, or
unwanted chemicals that remains with API’s6
drug substance is defined as-“any component
chemical entity defined as the new drug
impurities present in APIs recently, not onlyimpurities present in APIs recently, not only
profile has become essential as per various
chemicals, even in small amount, may influence the
products.products.
impurity is considered as any other organic
or ingredients, arise out of synthesis or
API’s” 9/10/2018

 By product;
 Degradation product;
 Interaction product;
 Intermediates;
 Related product; Related product;
 Transformation product;
 Penultimate product;
7
Degradation product;
Transformation product;
9/10/2018

Types of impurities and Sources
Sr. No. Types
1 Process related drug substances1 Process related drug substances
2 Process related drug product
3 Degradation drug substance/
product
4 Degradation drug product
8
Types of impurities and Sources (As per ICH guidelines) :
Sources
substances - Organic; starting materialsubstances - Organic; starting material
- Intermediate
- By product
- Impurity in starting material
product - Organic/ Inorganic
- Reagents/ Catalyst- Reagents/ Catalyst
Degradation drug substance/ -Organic
- Degradation product
- Excipients interaction
9/10/2018

Sources of Impurities....................
1. Crystallization related impurities
2. Stereochemistry related impurities2. Stereochemistry related impurities
3. Residual solvent
4. Synthetic intermediate & by product
5. Formulation related impurities
6. Impurities arise during storage6. Impurities arise during storage
7. Method related impurities
8. Functional group related typical degradation
9
Sources of Impurities....................
degradation
9/10/2018

Official method for Test for purity.......................
1. Color, Odor & Taste
2. Physicochemical constant2. Physicochemical constant
3. Acidity, Alkalinity & pH
4. Anions & Cations
5. Limits of insoluble matter
6. Limit of soluble matter6. Limit of soluble matter
7. Limit of non-volatile matter
8. Ash value
9. Limit of residue on ignition
10
Official method for Test for purity.......................
Physicochemical constantPhysicochemical constant
Acidity, Alkalinity & pH
Limits of insoluble matter
Limit of soluble matterLimit of soluble matter
volatile matter
Limit of residue on ignition
9/10/2018

What is Limit Test.......?
• It is a type of test in which compared opalescence turbidity or color with the
standard as a prescribed in pharmacopoeias.
• The extent of opalescence, turbidity and color is affected by the presence of
other impurities present in the substance, variation in time and method of
performance of the test. Therefore no numerical values for the limit in these tests
are prescribed in the pharmacopoeia.
• Limit test are performed in an aqueous solution or extract or in media
in monograph of pharmacopoeia.11
compared opalescence turbidity or color with the
as a prescribed in pharmacopoeias.
The extent of opalescence, turbidity and color is affected by the presence of
other impurities present in the substance, variation in time and method of
performance of the test. Therefore no numerical values for the limit in these tests
aqueous solution or extract or in media as specified
9/10/2018

Definition .......
Limits tests are quantitative or semi quantitative
and control small quantities of impurity, which are likely to be present in
the substances.
Types:
1. Tests in which there is no visible reaction1. Tests in which there is no visible reaction
2. Comparison methods
3. Quantitative determinations
12
semi quantitative tests designed to identify
of impurity, which are likely to be present in
no visible reactionno visible reaction
9/10/2018

Limit test for chloride:......DownloadsLimit test
Principle: The test is based upon the precipitation
presence of dil. nitric acid & comparison ofpresence of dil. nitric acid & comparison of
chloride. The opalescence in sample solution
solution for substance to pass the limit test.
Reaction:
14
Limit test vidioLab Test for Chloride Ions.mp4
precipitation of chloride with silver nitrate in the
of the opalescence solution so obtained withof the opalescence solution so obtained with
solution of substance should be less than of standard
9/10/2018

Test sample
1. Specific weight of compound is
dissolved in water or solution is
Procedure:
prepared as directed in the
pharmacopoeia and transferred in
Nessler cylinder.
2. Add 1ml of dil. nitric acid
3. Dilute to 50ml in Nessler cylinder3. Dilute to 50ml in Nessler cylinder
4. Add 1ml of AgNO3 solution
5. Keep aside for 5 min
6. Observe the Opalescence/Turbidity
15
Standard compound
1. Take 1ml of 0.05845 % W/V solution of
sodium chloride in Nessler cylinder.
2. Add 1ml of dil. nitric acid
3. Dilute to 50ml in Nessler cylinder3. Dilute to 50ml in Nessler cylinder
4. Add 1ml of AgNO3 solution
9/10/2018

Fig. Nessler cylinder
Test StandardTest Standard
16
Fig. Nessler cylinder
Test StandardTest Standard
9/10/2018

Observation:
The opalescence produce in sample solution should not be greater than standard solution. If opalescence
produces in sample solution is less than the standard
chloridechloride
and visa versa.
Reasons:
 Nitric acid is added in the limit test of chloride
precipitate
to make solution turbid at the end of process. Nitric acid
insoluble in
Nitric acid.
 B.P. Make use of 1 mL of 0.01 N HCl as standard
17
The opalescence produce in sample solution should not be greater than standard solution. If opalescence
standard solution, the sample will pass the limit test of
chloride to make solution acidic and helps silver chloride
acid dissolved other impurities & AgCl precipitate is
solution & 1 mL 5% Silver nitrate solution.
9/10/2018

Limit Test for Sulphates:......Downloads
Principle: The limit test of sulphate depends on the precipitation of the sulphate with
barium sulphate with barium chloride as barium sulphate in presence of hydrochloricbarium sulphate with barium chloride as barium sulphate in presence of hydrochloric
acid & traces of barium sulphate. Or
Test based on the reaction of soluble sulphate with barium chloride in presence of dil.
HCl to form barium sulphate which appears as solid particles (turbidity) in the solution.
Reaction:
19
DownloadsLimit test vidioTest for a sulfate.mp4
The limit test of sulphate depends on the precipitation of the sulphate with
barium sulphate with barium chloride as barium sulphate in presence of hydrochloricbarium sulphate with barium chloride as barium sulphate in presence of hydrochloric
Test based on the reaction of soluble sulphate with barium chloride in presence of dil.
HCl to form barium sulphate which appears as solid particles (turbidity) in the solution.
9/10/2018

Procedure:
Test sample
1. Specific weight of compound is
dissolved in water or solution is
prepared as directed in the
pharmacopoeia and transferred in
Nessler cylinder.
2. Add 2ml of dilute hydrochloric acid
3. Dilute to 45 ml in Nessler cylinder3. Dilute to 45 ml in Nessler cylinder
4. Add 5ml of barium sulphate reagent
20
Standard compound
1. Take 1ml of 0.1089 % W/V solution of
potassium sulphate in Nessler cylinder
1. Add 2ml of dilute hydrochloric acid
2. Dilute to 45 ml in Nessler cylinder2. Dilute to 45 ml in Nessler cylinder
3. Add 5ml of barium sulphate reagent
9/10/2018

 Barium sulphate reagent contains barium chloride, sulphate free alcohol & small amount of
potassium sulphate.
Observation:
The turbidity produce in sample solution should not be greater than standard solution. If turbidityThe turbidity produce in sample solution should not be greater than standard solution. If turbidity
produces in sample solution is less than the standard solution, the sample will pass the limit test of
sulphate and vice versa.
Reasons:
 Hydrochloric acid helps to make solution acidic.
 Potassium sulphate is used to increase the sensitivity of the test by giving ionic
concentration in the reagent.
 Alcohol helps to prevent super saturation.
21
Barium sulphate reagent contains barium chloride, sulphate free alcohol & small amount of
The turbidity produce in sample solution should not be greater than standard solution. If turbidityThe turbidity produce in sample solution should not be greater than standard solution. If turbidity
produces in sample solution is less than the standard solution, the sample will pass the limit test of
helps to make solution acidic.
is used to increase the sensitivity of the test by giving ionic
9/10/2018

Limit test for Iron:
Principle: The test based upon the reaction of iron in an ammoniacal solution with
thioglycollic acid in a solution buffered with ammonium citrate ether which forms
to deep reddish purple color complex of iron
specified amount of substance from the test is compared by viewing vertically with a
standard.
Reaction:Reaction:
24
The test based upon the reaction of iron in an ammoniacal solution with
thioglycollic acid in a solution buffered with ammonium citrate ether which forms a pink
of iron-thioglycollate . The color produce from
specified amount of substance from the test is compared by viewing vertically with a
9/10/2018

Test
1. Sample is dissolved in specific amount of
water and then volume is made up to 40 ml
2. Add 2 ml of 20 % w/v of citric acid (iron
free).
3. Add 2 drops of thioglycollic acid.
4. Add ammonia to make the solution alkaline
and adjust the volume to 50 ml
5. Keep aside for 5 min.
6. Color developed is viewed vertically and
compared with standard solution.
Earlier amoniumthiocyanate reagent was used for the limit test of iron. Since thioglycollic
acid is more sensitive reagent, it has replaced ammonium thiocyanate in the test.
25
Standard
1. 2 ml of standard solution of iron diluted
with water up to 40ml.
2. Add 2 ml of 20 % w/v of citric acid (iron
free).
3. Add 2 drops of thioglycollic acid.
4. Add ammonia to make the solution alkaline
and adjust the volume to 50 ml
5. Keep aside for 5 min.
6. Color developed is viewed vertically and
compared with standard solution.
Earlier amoniumthiocyanate reagent was used for the limit test of iron. Since thioglycollic
acid is more sensitive reagent, it has replaced ammonium thiocyanate in the test.
9/10/2018

Observation:
The purple color produce in sample solution should not be greater than standard
solution. If purple color produces in sample solution is less than the standardsolution. If purple color produces in sample solution is less than the standard
solution, the sample will pass the limit test of iron and vice versa.
Reasons:
1. Citric acid helps precipitation of iron by ammonia by forming a complex with it.1. Citric acid helps precipitation of iron by ammonia by forming a complex with it.
2. Thioglycollic acid helps to oxidize iron (II) to iron (III).
3. Ammonia to make solution alkaline
26
The purple color produce in sample solution should not be greater than standard
solution. If purple color produces in sample solution is less than the standardsolution. If purple color produces in sample solution is less than the standard
solution, the sample will pass the limit test of iron and vice versa.
1. Citric acid helps precipitation of iron by ammonia by forming a complex with it.1. Citric acid helps precipitation of iron by ammonia by forming a complex with it.
2. Thioglycollic acid helps to oxidize iron (II) to iron (III).
9/10/2018

Limit test for Heavy Metals :
Principle: Limit test of heavy metals is based on the reaction of metallic impurities with
hydrogen sulphide in acidic medium to form brownish colour solution
response to this test are lead, mercury , bismuth, arsenic, antimony , tin, cadmium,
silver , copper , and molybdenum.
The metallic impurities in substances are expressed as parts of lead per millionThe metallic impurities in substances are expressed as parts of lead per million
parts of the substance. The usual limit as per Indian Pharmacopoeia is 20 ppm
27
Limit test of heavy metals is based on the reaction of metallic impurities with
brownish colour solution. Metals that
response to this test are lead, mercury , bismuth, arsenic, antimony , tin, cadmium,
The metallic impurities in substances are expressed as parts of lead per millionThe metallic impurities in substances are expressed as parts of lead per million
The usual limit as per Indian Pharmacopoeia is 20 ppm.
9/10/2018

Procedure: The I.P. has adopted three methods for the limit test of heavy metals.
Method-I: Use for the substance which gives clear colorless solution under the specific condition
Test sample
1. Solution is prepared as per the monograph and 25 ml is 1.1. Solution is prepared as per the monograph and 25 ml is
transferred in Nessler’s cylinder
2. Adjust the pH between 3 to 4 by adding dilute acetic acid
‘Sp’ or dilute ammonia solution ‘Sp’
3. Dilute with water to 35 ml
4. Add freshly prepared 10 ml of hydrogen sulphide
1.
2.
3.
4.
solution
6. Allow to stand for five minutes
7. View downwards over a white surface
5.
6.
7.
28
The I.P. has adopted three methods for the limit test of heavy metals.
the substance which gives clear colorless solution under the specific condition.
Standard compound
1. Take 2 ml of standard lead solution and dilute to 25 ml1. Take 2 ml of standard lead solution and dilute to 25 ml
with water
2. Adjust the pH between 3 to 4 by adding dilute acetic acid
‘Sp’ or dilute ammonia solution ‘Sp’
4. Add freshly prepared 10 ml of hydrogen sulphide
solution
9/10/2018

Observation:
The color produce in sample(Test) solution should
solution. If color produces in sample solution is
sample will pass the limit test of heavy metals & vice versa.
Method II:
Use for the substance which do not give clear colorless solution under the specific
condition.
29
solution should not be greater than standard
solution. If color produces in sample solution is less than the standard solution, the
sample will pass the limit test of heavy metals & vice versa.
Use for the substance which do not give clear colorless solution under the specific
9/10/2018

Test sample
1. Weigh specific quantity of test substance, moisten with
sulphuric acid and ignite on a low flame till completely
charred.
Add few drops of nitric acid and heat to 500 °C
Allow to cool and add 4 ml of hydrochloric acid and evaporateAllow to cool and add 4 ml of hydrochloric acid and evaporate
to dryness Moisten the residue with 10 ml of hydrochloric acid
and digest for two minutes
Neutralize with ammonia solution and make just acid with
acetic acid
2. Adjust the pH between 3 to 4 and filter if necessary
4. Add freshly prepared 10 ml of hydrogen sulphide solution
7. View downwards over a white surface30
Standard compound
1. Take 2 ml of standard lead solution and dilute to 25 ml with
water
2. Adjust the pH between 3 to 4 by adding dilute acetic acid ‘Sp’
or dilute ammonia solution ‘Sp’
4. Add freshly prepared 10 ml of hydrogen sulphide solution
7. View downwards over a white surface. 9/10/2018

Observation:
The color produce in sample solution should not be greater than standard solution. If
color produces in sample solution is less than the standard solution, the sample will pass
the limit test of heavy metals and vice versa.
Method III:
Use for the substance which gives clear colorless solution in sodium hydroxide solution.
31
color produces in sample solution is less than the standard solution, the sample will pass
the limit test of heavy metals and vice versa.
Use for the substance which gives clear colorless solution in sodium hydroxide solution.
9/10/2018

Test sample
1. Solution is prepared as per the monograph and 25
ml is transferred in Nessler’s cylinder or weigh
specific amount of substance and dissolve in 20 ml
of water and add 5 ml of dilute sodium hydroxideof water and add 5 ml of dilute sodium hydroxide
solution
2. Make up the volume to 50 ml with water
3. Add 5 drops of sodium sulphide solution
4. Mix and set aside for 5 min
5. View downwards over a white surface5. View downwards over a white surface
Observation:
color produces in sample solution is less than the standard solution, the sample will
pass the limit test of heavy metals and vice versa.
32
Standard compound
specific amount of substance and dissolve in 20 ml
1. Take 2 ml of standard lead solution
2. Add 5 ml of dilute sodium hydroxide solution and
make up the volume to 50 ml with water
3. Add 5 drops of sodium sulphide solution3. Add 5 drops of sodium sulphide solution
4. Mix and set aside for 5 min
color produces in sample solution is less than the standard solution, the sample will
pass the limit test of heavy metals and vice versa.
9/10/2018

Limit Test of Arsenic
Principle:Principle:
Limit test of Arsenic is based on the reaction of
yellow stain on mercuric chloride paper in presence of
potassium iodide. It is also called as Gutzeit test
Arsenic, present as arsenic acid in the sample isArsenic, present as arsenic acid in the sample is
reducing agents like potassium iodide, stannous acid, zinc, hydrochloric acid
Arsenious acid is further reduced to arsine (gas)
mercuric chloride paper to give a yellow stain
33
Limit test of Arsenic is based on the reaction of arsenic gas with hydrogen ion to form
in presence of reducing agents like
Gutzeit test and. requires special apparatus
in the sample is reduced to arsenious acid byin the sample is reduced to arsenious acid by
potassium iodide, stannous acid, zinc, hydrochloric acid, etc.
arsine (gas) by hydrogen and reacts with
yellow stain.
9/10/2018

H3AsO4 + H2SnO2 → H
Arsenic acidArsenic acid
H3AsO3 + 3H2 →
Arsenious acid
The depth of yellow stain on mercuric chloride paper will depend upon theThe depth of yellow stain on mercuric chloride paper will depend upon the
arsenic present in the sample.
34
→ H3AsO3 + H2SnO3
Arsenious acidArsenious acid
→ AsH3 + 3H2O
Arsenious acid Arsine
on mercuric chloride paper will depend upon the quality ofon mercuric chloride paper will depend upon the quality of
9/10/2018

Procedure:
Test solution:
The test solution is prepared by dissolving specific amount in water
and stannated HCl (arsenic free) and kept in a wide mouthed bottle.
To this solution 1 gm of KI, 5 ml of stannous chloride acid solution
and 10 gm of zinc is added (all this reagents must be arsenic free)
Keep the solution aside for 40 min and stain obtained on mercuric
chloride paper is compared with standard solution.
Standard solution:Standard solution:
A known quantity of dilute arsenic solution is kept in wide mouthed
bottle and rest procedure is followed as described in test solution.
35
The test solution is prepared by dissolving specific amount in water
and stannated HCl (arsenic free) and kept in a wide mouthed bottle.
To this solution 1 gm of KI, 5 ml of stannous chloride acid solution
and 10 gm of zinc is added (all this reagents must be arsenic free)
Keep the solution aside for 40 min and stain obtained on mercuric
arsenic solution is kept in wide mouthed
bottle and rest procedure is followed as described in test solution.
9/10/2018

A ： approximately 60 ml generator bottle with 40 ml
B ： glass tube with 6.5 mm inner diameter
C and D
diameter and 18 mm outer diameter at the joint. Inner
Gutzeit apparatus
diameter and 18 mm outer diameter at the joint. Inner
joint and the outer joint form a concentric circle.
E ： rubber stopper
F ： narrow part of the glass tube B. Glass wool is
inserted up to this part.
G ： rubber board (Lead acetate cotton plug)G ： rubber board (Lead acetate cotton plug)
H ： clamp
Reasons:
Stannous chloride is used for complete evolution of arsine
Zinc, potassium iodide and stannous chloride is used as a reducing agent.
Hydrochloride acid is used to make the solution acidic
Lead acetate pledge or papers are used to trap any hydrogen sulphide which may be evolved along with arsine.36
approximately 60 ml generator bottle with 40 ml
indicating line.
glass tube with 6.5 mm inner diameter
C and D ： a ground joint glass tube with 6.5 mm inner
diameter and 18 mm outer diameter at the joint. Innerdiameter and 18 mm outer diameter at the joint. Inner
joint and the outer joint form a concentric circle.
rubber stopper
narrow part of the glass tube B. Glass wool is
inserted up to this part.
rubber board (Lead acetate cotton plug)rubber board (Lead acetate cotton plug)
clamp
is used for complete evolution of arsine
is used as a reducing agent.
are used to trap any hydrogen sulphide which may be evolved along with arsine.9/10/2018

Limit test for Lead:
Lead is a most undesirable impurity in medical compounds and comes through use of
sulphuric acid, lead lined apparatus and glass bottles use for storage of chemicals.
Principle:
Limit test of lead is based on the reaction of
in alkaline solution to form lead dithizone complexin alkaline solution to form lead dithizone complex
Dithizone is green in color in chloroform and
color, so the resulting color at the end of process
Procedure:
37
Limit test for Lead:
Lead is a most undesirable impurity in medical compounds and comes through use of
sulphuric acid, lead lined apparatus and glass bottles use for storage of chemicals.
lead and diphenyl thiocabazone (dithizone)
lead dithizone complex which is read in color.lead dithizone complex which is read in color.
and lead-dithizone complex is violet in
, so the resulting color at the end of process is red.
9/10/2018

Test sample
1. A known quantity of sample solution is transferred in a
separating funnel
2. Add 6ml of ammonium citrate
3. Add 2 ml of potassium cyanide and 2 ml of
hydroxylamine hydrochloride
4. Add 2 drops of phenol red
5. Make solution alkaline by adding ammonia solution.
6. Extract with 5 ml of dithizone until it becomes green
7. Combine dithizone extracts are shaken for 30 mins with
30 ml of nitric acid & the chloroform layer is discarded30 ml of nitric acid & the chloroform layer is discarded
8. To the acid solution add 5 ml of standard dithizone
solution
9. Add 4 ml of ammonium cyanide
10. Shake for 30 mins
11. Observe the color38
Standard compound
1. A standard lead solution is prepared equivalent to the
amount of lead permitted in the sample under examination
2. Add 6ml of ammonium citrate
3. Add 2 ml of potassium cyanide and 2 ml of
hydroxylamine hydrochloride
4. Add 2 drops of phenol red
5. Make solution alkaline by adding ammonia solution.
6. Extract with 5 ml of dithizone until it becomes green
7. Combine dithizone extracts are shaken for 30 mins with
30 ml of nitric acid & the chloroform layer is discarded30 ml of nitric acid & the chloroform layer is discarded
8. To the acid solution add 5 ml of standard dithizone
solution
9. Add 4 ml of ammonium cyanide
10. Shake for 30 mins
11. Observe the color 9/10/2018

Observation:
The intensity of the color of complex, is depends on the amount of lead in the solution. The color
produce in sample solution should not be greater than standard solution. If color produces in sample
solution is less than the standard solution, the sample will pass the limit test of lead and vice versa.
Reasons:
Ammonium citrate, potassium cyanide, hydroxylamine hydrochloride
so interference and influence of other impurities have been eliminated.so interference and influence of other impurities have been eliminated.
Phenol red is used as indicator to develop the color at the end of process
Lead present as an impurities in the substance, gets separated bye extracting an alkaline solution with a
dithizone extraction solution.
39
The intensity of the color of complex, is depends on the amount of lead in the solution. The color
produce in sample solution should not be greater than standard solution. If color produces in sample
solution is less than the standard solution, the sample will pass the limit test of lead and vice versa.
Ammonium citrate, potassium cyanide, hydroxylamine hydrochloride is used to make pH optimum
so interference and influence of other impurities have been eliminated.so interference and influence of other impurities have been eliminated.
is used as indicator to develop the color at the end of process
present as an impurities in the substance, gets separated bye extracting an alkaline solution with a
9/10/2018

References:
1. IP 1996 & IP 2007; Vol-I
2. www.pharmaguideline.com2. www.pharmaguideline.com
3. http://www.web-formulas.com
4. https://hmc.usp.org/sites/default/files/documents/HMC/GCs
5. Pharmacopoeia/EUROPEAN PHARMACOPOEIA 7.0/DATA/20404E.PDF
40
https://hmc.usp.org/sites/default/files/documents/HMC/GCs-Pdfs/c211.pdf
Pharmacopoeia/EUROPEAN PHARMACOPOEIA 7.0/DATA/20404E.PDF
9/10/2018

Any Question..........?
Thank U.......Thank U.......
Any Question..........?
Thank U.......Thank U.......
9/10/2018

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