Test Procedures for Dosage Forms

Test Procedures for Dosage Forms: Basic tests describe procedures for testing pharmaceutical substances, medicinal plant materials, and pharmaceutical dosage forms. Basic tests are not, intended to replace the requirements of The International Pharmacopoeia or other pharmacopoeial monographs. These give an assurance of quality whereas, basic tests merely confirm identity.

Basic tests need not be carried out by fully qualified pharmacists or chemists, but they should be performed by people with some understanding of analytical chemistry such that acquired in courses for pharmaceutical assistants.

1. Allopurinol Tablets

Description: Each tablet usually contains 100 mg of allopurinol.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.30 gm of allopurinol.
• Grind the tablets, weigh out the above-calculated equivalent amount as powdered material, triturate it with 10 ml of sodium hydroxide (0.1 mol/L) VS, and filter. Acidify the filtrate with acetic acid (-60 g/L) TS, filter, wash the precipitate with 3 ml of dehydrated ethanol and allow drying in the air for 5 minutes. Then dry at 105°C for 3 hours and use the dried material as the test substance, dividing it into 6 equal parts.

Melting point: About 350°C.

Identity tests:

Procedures:

• Dissolve 1 part of the test substance in 5 ml of sodium hydroxide (~80 gm/L) TS, add 1 ml of alkaline potassio-mercuric iodide TS, heat to boiling and allow to stand; a yellow, flocculent precipitate is produced.
• Dissolve 4 parts of the test substance in a mixture of 2 ml of sodium hydroxide (-80 gm/L) TS and ml f water. Add 3 ml of citric acid (90 gm/L) TS and shake vigorously; a white precipitate is produced.
• Dissolve 1 part of the test substance in 25 ml of water by warming, cool, and filter. To 5 ml of the filtrate (keep the unused portion for test 4) add 1 ml of ammonia (-100 gm/L) TS and 1 ml of silver nitrate (40 gm/L) TS; a white precipitate is produced.
• To 5 ml of the filtrate from test 3, add 0.5 ml of copper (II) sulfate (160 gm/L) TS; a blue precipitate is produced.

Degradation test: Discoloration of the test material usually indicates gross degradation.

2. Amikacin Sulfate Injection

Description: The injection is a sterile solution usually containing 250 mg of amikacin sulfate in 1.0 ml of a suitable vehicle.

Preparation of the sample:

• Pool the contents of the ampoules equivalent to 1.0 gm of amikacin sulfate and use directly as test solution 1, dividing it into 2 equal volumes.
• Dilute 1 volume of test solution 1 to 25 ml with water and use it as test solution 2.

Identity tests:

Procedures:

• To 3 ml of test solution 2, add 1 ml of sodium hydroxide (-80 gm/L) TS, mix and add 2 ml of cobalt (II) nitrate (10 gm/L) TS; a violet color is produced.
• To 1 volume of test solution 1, add slowly 2 ml of anthrone TS; a bluish violet color is produced.
• To 2 ml of test solution 2, add a few drops of barium chloride (50 gm/L) TS; a white precipitate is produced which is practically insoluble in hydrochloric acid (-250 gm/L) TS.

Degradation test: Discoloration and a change in the physical state of test solution 1 usually indicategross degradation.

3. Azathioprine Sodium Powder For Injection

Description: Each vial contains a sterile powder of azathioprine sodium usually equivalent to 50-100 mg of azathioprine.

Preparation of the sample:

• Weigh the contents of 1 vial and calculate the amount equivalent to 0.05 gm of azathioprine.
• Empty the vials, weigh out the above-calculated equivalent amount and use it directly as the test substance, dividing it into 3 equal parts.
• Dissolve 1 part of the test substance in 100 ml of water and use it as the test solution.

Identity tests:

Procedures:

• To 5 ml of the test solution, add 1 ml of hydrochloric acid (~70 gm/L) TS and 10 mg of zinc powder and allow to stand for 5 minutes; the color of the solution changes to yellow. Filter, cool in ice and add 3-4 drops of sodium nitrite (10 gm/L) TS and 5-6 drops of hydrochloric acid (~70 gm/L) TS. Shake and allow to stand for 2 minutes. Then add about 0.25 gm of urea, shake and again allow to stand for 2 minutes. Add 0.5 ml of N-(1-naphthyl) ethylenediamine/ethanol TS; a red-violet solution is produced.
• Transfer 2 parts of the test substance to a test tube, add 0.05 gm of potassium nitrate and about 0.1 gm of potassium hydroxide, and heat carefully until fused. Cool dissolve the residue in 20 ml of water and filter. To 5 ml of the filtrate, add 1.5 ml of hydrochloric acid (-70 gm/L) TS and 5-6 drops of barium chloride (50 gm/L) TS; white turbidity appears.
• To about 1 ml of the test solution, add 0.5 ml of phosphotungstic acid (10 gm/L) TS and 0.5 ml of hydrochloric acid (-70 gm/L) TS; a white precipitate is produced.

Degradation test: Discoloration and a change in the physical state of test solution 1 usually indicate gross degradation.

4. Barium Sulfate Powder For Suspension

Description: A white or creamy white powder, bulky or granular.

Preparation of the sample: Use the powder directly as the test substance.

Identity tests:

Procedures:

• Suspend 20 mg of the test substance in about 1 ml of hydrochloric acid (-420 gm/L) TS and introduce it into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; a pale green color appears in the flame.
• To 0.30 gm of the test substance, add 10 ml of water and about 1 gm of anhydrous sodium carbonate, boil for 5 minutes, and filter. Acidify the filtrate with hydrochloric acid (-420 gm/L) TS and add 1 ml of barium chloride (50 gm/L) TS; a white precipitate is produced.
• To about 1 gm of the test substance, add 1 ml of acetic acid (-300 gm/L) TS and 25 ml of water and boil. While shaking, cool, and filter, if the filtrate is turbid, repeat the filtration until a clear solution is obtained and then add 1 ml of sulfuric acid (-100 gm/L) TS; no opalescence is produced within 30 minutes (absence of soluble barium salts).

Degradation test: Discoloration and a change in the physical state of the test solution usually indicate gross degradation.

5. Beclometasone Dipropionate Inhalation (Aerosol)

Description: The inhalation, supplied in a pressurized canister, contains a fine suspension of beclometasone dipropionate in a suitable propellant, usually equivalent to 50 µg per spray dose.

Preparation of the sample:

• Place 25 ml of ethanol (-750 gm/L) TS in a small beaker and expel under the surface of the solvent 60 spray doses equivalent to about 3 mg of beclometasone dipropionate. Use this solution as the test solution.
• Evaporate 10 ml of the test solution and use the residue as test substance 1.
• Evaporate 15 ml of the test solution and use the residue as test substance 2.

Identity tests:

Procedures:

• Dissolve test substance 1 in about 2 ml of sulfuric acid (-1760 gm/L) TS and allow to stand for 5 minutes; a dark reddish-brown solution is produced. Very cautiously pour the solution into 10 ml of water, a very light bluish grey precipitate is produced.
• Dissolve test substance 2 in 20 ml of ethanol (-750 gm/L) TS and add 10 ml of tetramethylammonium hydroxide/ethanol TS and 1.0 ml of triphenyl tetrazolium chloride/ethanol TS, shaking thoroughly after each addition. Allow to stand in the dark for 20 minutes; the red color is produced.

Degradation test: Discoloration and a change in the physical state of the test solution usually indicate gross degradation.

6. Calcium Gluconate Injection

Description: The injection is a sterile solution usually containing 100 mg of calcium gluconate in 1.0 mil of a suitable vehicle.

Preparation of the sample: Dilute the contents of 1 ampoule to obtain a concentration of 10 mg of calcium gluconate in 1 ml of water and use it as the test solution.

Identity tests:

Procedures:

• Evaporate 1 ml of the test solution to dryness over a water bath, add 5 mg of 2-naphthol dissolved in about 1 ml of sulfuric acid (-1760 gm/L) TS, and heat in a water bath for 1 minute; a dark blue-green color is produced.
• To 2 ml of silver nitrate (40 gm/L) TS, add ammonia (~100 gm/L) TS, drop by drop, until the initially formed brown precipitate just dissolves. Add 1 ml of the test solution and heat to boiling for 1-2 minutes; a silver mirror is produced.
• To 2 ml of the test solution, add 5 drops of ammonium oxalate (25 gm/L) TS; a white precipitate is produced. To a portion of the precipitate add a few drops of hydrochloric acid (-70 gm/L) TS; the precipitate dissolves. To the remaining precipitate add a few drops of acetic acid (~300 gm/L) TS; the precipitate is practically insoluble.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

7. Cetrimide Cream

Description: The cream usually contains 5 mg of cetrimide in 1.0 gm of a suitable cream base.

Preparation of the sample:

• Withdraw and weigh an amount equivalent to 10 mg of cetrimide and use it directly as the test substance.
• Withdraw and weigh an amount equivalent to 20 mg of cetrimide, transfer to a test tube, add 10 ml of sodium chloride (100 gm/L) TS and shake thoroughly. While. warming in a water bath, keep shaking to effect separation of the emulsion. Remove the test tube from the bath, cool, filter the aqueous phase and use the filtrate as the test solution.

Melting point: About 250°C.

Identity tests:

Procedures:

• Transfer the test substance to a stoppered test tube and shake with 10 ml of water, a large amount of foam is produced (keep the solution for test 2).
• To 5 ml of the solution from test 1, add 5 ml of nitric acid (~130 gm/L) TS, shake, filter, and add 5 ml of silver nitrate (40 gm/L) TS; a faint opalescence is produced. Allow to stand in the dark for 30 minutes; a faint yellow-grey precipitate is produced.
• To 5 ml of water, add 1 ml of sulfamic acid (100 gm/L) TS, 1 drop of methyl orange/ethanol TS and 2 ml of dichloromethane R and shake; the dichloromethane layer remains colorless. Add 3 ml of the test solution (keep the unused portion for test 4) to the tube, shake and allow the layers to separate; a yellow color is produced in the dichloromethane layer.
• Place the remaining test solution from test 3 over a water bath, reduce the volume to about 2 ml and add 2 ml of potassium ferricyanide (50 gm/L) TS, a yellow precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

8. Cimetidine Injection

Description: The injection is a sterile solution usually containing 200 mg of cimetidine in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 0.4 gm and use directly as the test solution, dividing it into 2 equal volumes.

Identity tests:

Procedures:

• Place 1 volume of the test solution in a test tube and evaporate to dryness over a water bath. Ignite the residue; the vapors produced darken moistened lead nitrate paper.
• Dilute 1 volume of the test solution with 10 ml of water. To 1 ml (keep the unused portion for test 3), add 1 drop of ammonia (-100 gm/L) TS and 1 drop of copper (II) sulfate (160 gm/L) TS and heat in a water-bath; a greyish green precipitate is produced which is soluble in an excess of ammonia (~100 gm/L) TS.
• To 1 ml of the diluted solution from test 2, add a few drops of potassium iodobismuthate/acetic acid TS; an orange precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

9. Dextran 70 Injection

Description: The injection is a sterile solution usually containing 6 gm of dextran 70 in 100 ml of a suitable vehicle (normally dextrose or sodium chloride solution).

Preparation of the sample: Pool a volume equivalent to 0.12 gm of dextran 70 and use it directly as the test solution, dividing it into 4 equal volumes. 

Identity tests:

Procedures:

For dextran 70 in dextrose solution:

• To 1 volume of the test solution, add 5 ml of potassio-cupric tartrate TS and boil; a brick-red precipitate is formed. Filter and to the filtrate, add about 15 ml of hydrochloric acid (-420 gm/L) TS. Boil for 5 minutes, cool, and neutralize by adding sodium carbonate until the effervescence ceases. Add 2 ml of potassio-cupric tartrate TS and boil again; a brick-red precipitate is again produced.

For dextran 70 in sodium chloride solution:

• To 1 volume of the test solution, add 5 ml of potassio-cupric tartrate TS and boll the solution remains greenish and no precipitate is formed. Dilute a further 0.5 ml of the test solution to 5 ml with water and add about 0.5 ml of hydrochloric acid (~420 gm/L) TS. Boil for 5 minutes, cool, and neutralize by adding sodium carbonate until the effervescence ceases. Add 2 ml of potassio-cupric tartrate TS and boil again; a brick-red precipitate is produced.
• Introduce the test solution into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color.
• Acidify 1 volume of the test solution with a small volume of nitric acid (-130 gm/L) TS and add 2 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash it with water and add a few drops of ammonia (~100 gm/L) TS; the precipitate dissolves.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

10. Diphenhydramine Hydrochloride Tablets

Description: Each tablet usually contains 25-50 mg of diphenhydramine hydrochloride.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.20 gm of diphenhydramine hydrochloride.
• Grind the tablets, weigh out the above-calculated equivalent amount as a powdered material and use it directly as the test substance, dividing it into 4 equal parts.

Melting point: About 171°C. Identity tests:

Procedures:

• Place a small quantity of the test substance on a white test plate and add 1 drop of a mixture of about 0.5 ml of nitric acid (~1000 gm/L) TS and about 0.5 ml of sulfuric acid (~1760 gm/L) TS; a momentary violet color is produced which changes to red and finally to yellow.
• To 2 parts of the test, the substance adds 5 ml of water, shake and filter. To the filtrate add 3 ml of hydrochloric acid (~250 gm/L) TS and boil for 3 minutes. Cool the test tube in ice and scratch the inside of the tube with a glass rod to induce crystallization. Separate the crystals and dry them over silica gel, desiccant; melting point, about 64°C. If the melting point is lower than 64°C, recrystallize from 1-2 ml of water.
• To 1 part of the test substance, add 5 ml of water, shake and filter. To the filtrate add 0.5 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash it with water and add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves.

Degradation test: Discoloration of the test solution usually indicates gross degradation,

11. Epinephrine Hydrogen Tartrate Injection

Description: The injection is a sterile solution of epinephrine hydrogen tartrate, usually containing the equivalent of 1.0 mg of epinephrine in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 10 mg of epinephrine hydrogen tartrate; if necessary, reduce the volume by evaporation to 10 ml or dilute to 10 ml with water. Use directly as the test solution.

Identity tests:

Procedures:

• To 5 ml of the test solution, add 1-2 drops of ferric chloride (25 gm/L) TS; a green solution is produced. Add 1 drop of ammonia (~260 gm/L) TS; the color changes to dark red.
• To 2 ml of the test solution, add 1 ml of sulfuric acid (-5 gm/L) TS and 3 ml of ammonium molybdate (95 gm/L) TS and mix; an orange color is produced. Then add slowly, 2 ml of sodium hydroxide (-80 gm/L) TS while mixing, a yellow-green solution is produced.
• To 2 ml of the test solution, add 2 ml of potassium bromide (100 gm/L) TS, 2 ml of resorcinol (20 gm/L) TS, and 3 ml of sulfuric acid (-1760 gm/L) TS. Heat in a water bath for 5-10 minutes; a dark blue color is produced which changes to red when the solution is cooled and poured into water.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

12. Ferrous Fumarate Tablets

Description: Each tablet contains ferrous fumarate, usually equivalent to 60 mg of iron.

Preparation of the sample:

• Weigh 1 tablet and calculate the amounts equivalent to 0.5 gm and 0.05 gm of ferrous fumarate.
• Grind the tablets, weigh out the above-calculated equivalent amounts as a powdered material and use directly, 0.5 gm test substance 1 and 0.05 gm as a test substance 2.

Melting point: About 280°C.

Identity tests:

Procedures:

• To test substance 1, add 20 ml of sulfuric acid (-100 gm/L) TS and heat in a water bath for 15 minutes. Filter while hot and cool the filtrate in ice; a white precipitate is produced (keep the filtrate for test 2). Wash the precipitate with acidified water and dry at 105°C. Dissolve the precipitate in 5 ml of sodium carbonate (50 gm/L) TS and add 0.5 ml of potassium permanganate (10 gm/L) TS; the color of the permanganate fades and a brownish solution is produced.
• To 2 ml of the filtrate obtained in test 1, add 2 ml of potassium ferricyanide (50 gm/L) TS; an intense dark blue precipitate is produced which is insoluble in hydrochloric acid (~70 gm/L) TS.
• Mix test substance 2 with 0.10 gm of resorcinol, add 5-10 drops of sulfuric acid (~1760 gm/L) TS, and heat gently; a deep red, semi-solid mass is produced. Cool, add 25 ml of water, swirl to dissolve, and filter. To 1 ml of the filtrate, add 10 ml of water and mix; an orange-yellow solution is produced which exhibits a green fluorescence. Make the solution alkaline by adding a few drops of sodium hydroxide (~80 gm/L) TS; a red solution is produced which exhibits a green fluorescence.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

13. Gentamicin Sulfate Injection

Description: The injection is a sterile solution usually containing 10-40 mg of gentamicin sulfate in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 0.20 gm of gentamicin sulfate; if necessary, reduce the volume by evaporation to about 5 ml or dilute to 5 ml with water. Use directly as the test solution.

Identity tests:

Procedures:

• To 1 ml of the test solution, add a solution of 5 mg of 1-naphthol dissolved in 1 drop. of ethanol (~750 gm/L) TS, 4 drops of water, and about 0.5 ml of sulfuric acid (-1760 gm/L) TS; a yellow color is produced.
• To 1 ml of the test solution, add a solution of 20 mg of triketohydrindene hydrate dissolved in 2 ml of water and 0.10 gm of sodium acetate. Mix and heat in a water bath for 5 minutes; a dark violet color is produced.
• Dilute 1 ml of the test solution with 1 ml of water and add 5 drops of alkaline potassio-mercuric iodide TS; a yellowish-white, turbid solution is produced.
• Dilute 1 ml of the test solution with 2 ml of water and add 5 drops of hydrochloric acid (~70 gm/L) TS and 5 drops of barium chloride (50 gm/L) TS; a white precipitate is produced,

14. Hydrocortisone Ointment

Description: The ointment usually contains 10-25 mg of hydrocortisone in 1.0 gm of a suitable ointment base.

Preparation of the sample: Withdraw and weigh an amount equivalent to 20 mg of hydrocortisone, add 10 ml of ethanol (-750 gm/L) TS, and heat in a water bath for 5 minutes with frequent shaking. Cool to solidify the ointment base, filter, and use the filtrate as the test solution, dividing it into 4 equal volumes.

Melting point: About 60°C.

Identity tests:

Procedures:

• Evaporate 1 volume of the test solution to dryness over a water bath. Add about 2 ml of sulfuric acid (-1760 gm/L) TS and allow it to stand for 5 minutes; a yellow solution is produced with a greenish fluorescence. Very cautiously pour the solution into 10 ml of water; the color of the solution changes to brownish yellow, but the fluorescence remains (certain excipients may interfere with the reaction and the color of the solution may fade to nearly colorless).
• Evaporate 1 volume of the test solution to dryness over a water bath. Add about 1 ml of phosphoric acid (~1440 gm/L) TS and heat cautiously; the solution is initially colorless, changes to yellow, and shows a slightly greenish fluorescence.
• Evaporate 2 volumes of the test solution to about 2 ml over a water bath and add an equal volume of potassio-cupric tartrate TS; an orange-red precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

15. Hydrocortisone Sodium Succinate Powder For Injection

Description: Each vial contains a sterile powder usually equivalent to 100 mg of hydrocortisone sodium succinate.

Preparation of the sample:

• Weigh the contents of 1 vial and calculate the amount equivalent to 0.10 gm of hydrocortisone sodium succinate.
• Empty the vial, weigh out the above-calculated equivalent amount and use it directly as the test substance.

Identity tests:

Procedures:

• Dissolve about 2 mg of the test substance in 1 ml of alkaline potassio-mercuric iodide TS; a dark precipitate is produced.
• Dissolve a small quantity of the test substance in about 2 ml of sulfuric acid (-1760 gm/L) TS and allow it to stand for 5 minutes; a yellow solution with a greenish fluorescence is produced. Very cautiously pour the solution into 10 ml of water, the color of the solution changes to brownish yellow, but the fluorescence remains (certain excipients may interfere with the reaction and the color may fade to nearly colorless within a very short period).
• Dissolve a small quantity of the test substance in about 1 ml of phosphoric acid (-1440 gm/L) TS and heat cautiously; a yellow solution with a pale greenish fluorescence is produced.
• Dissolve about 2 mg of the test substance in 1 ml of water and introduce the solution into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color.
• Heat carefully 10 mg of the test substance with 1 drop of water, 10 mg of resorcinol, and 3 drops of sulfuric acid (~1760 gm/L) TS, cool and add 2 ml of water. Cool again and pour the solution into a mixture of 100 ml of water and 1 ml of sodium hydroxide (-400 gm/L) TS; a yellowish-green fluorescence appears.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

16. Indomethacin Tablets

Description: Each tablet usually contains 25 mg of indomethacin.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.05 gm of indomethacin.
• Grind the tablets, weigh out the above-calculated equivalent amount as a powdered material and use it directly as the test substance, dividing it into 2 equal parts.

Melting point: About 162°C.

Identity tests:

Procedures:

• To 1 part of the test, the substance adds 1 ml of water and 1 drop of sodium hydroxide (-80 gm/L) TS, shake and filter. To the filtrate, add 1 ml of sodium nitrite (10 gm/L) TS, allow to stand for 5 minutes, and cautiously add 0.5 ml of hydrochloric acid (~250 gm/L) TS; a green color is produced.
• Mix 1 part of the test substance with 2 ml of water and 2 ml of sodium hydroxide (-80 gm/L) TS; a strong yellow color is produced which fades rapidly.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

17. Iron Dextran Injection

Description: The injection is a sterile solution of iron dextran, usually containing the equivalent of 50 mg of iron in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 0.15 gm of iron; if necessary, reduce the volume to about 3 ml or dilute with water to 3 ml. Use directly as the test solution.

Identity tests:

Procedures:

• Place 1 ml of the test solution on a watch glass and add 2 drops of ammonia (-260 gm/L) TS; no precipitate is observed. Add about 2 ml of hydrochloric acid (-420 gm/L) TS, mix and add about 2 ml of ammonia (-260 gm/L) TS: a reddish-brown precipitate is produced.
• Acidify 1 ml of the test solution with hydrochloric acid (-70 gm/L) TS and add 1 ml of ammonium thiocyanate (75 gm/L) TS; a blood-red color is produced. Extract with 5 ml of amyl alcohol and add a few drops of mercuric chloride (65 gm/L) TS or phosphoric acid (~1440 gm/L) TS; the color is discharged.
• Dilute about 0.2 ml of the test solution with 20 ml of water. To 10 ml of this solution, add 4 drops of hydrochloric acid (~420 gm/L) TS and boil for 30 seconds. Cool rapidly and add 4 ml of ammonia (~260 gm/L) TS and 10 ml of hydrogen sulfide TS. Boil to remove the excess hydrogen sulfide, cool, and filter. Boil 5 ml of the filtrate with 5 ml of potassio-cupric tartrate TS; the color of the solution remains greenish and no precipitate is produced. Boil a further 5 ml of the filtrate with about 0.5 ml of hydrochloric acid (~420 gm/L) TS for 5 minutes, cool, add 2.5 ml of sodium hydroxide (-80 gm/L) TS and 5 ml of potassio-cupric tartrate TS and boil again; a reddish precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation,

18. Ketamine Hydrochloride Injection

Description: The injection is a sterile solution of ketamine hydrochloride, usually containing the equivalent of 50 mg of ketamine in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 0.15 gm of ketamine hydrochloride and use directly as the test solution, dividing it into 3 equal volumes.

Melting point: About 261°C.

Identity tests:

Procedures:

• To one-third of 1 volume of the test solution, add a few drops of sodium hydroxide (-80 gm/L) TS; white turbidity is produced. Add a few drops of methanol; the turbidity disappears.
• To one-third of 1 volume of the test, the solution adds 0.5 ml of trinitrophenol/ethanol TS; a yellow precipitate is produced.
• Acidify one-third of 1 volume of the test solution with a small volume of nitric acid (~130 gm/L) TS and add 2 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash it with water and add an excess of ammonia (~100 gm/L) TS; the precipitate dissolves.
• Evaporate 2 volumes of the test solution to dryness. Recrystallize the residue from ethanol (~750 gm/L) TS and dry at 105°C for 2 hours.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

19. Lidocaine Hydrochloride Jelly

Description: The jelly usually contains 20-40 mg of lidocaine hydrochloride in 1.0 gm of a suitable water-soluble, viscous base.

Preparation of the sample:

• Add 10-15 ml of water to a separator, add a quantity of the jelly equivalent to 0.15 gm of lidocaine hydrochloride and mix. Add 2.0 ml of ammonia (~100 gm/L) TS and extract with 2 portions of 30 ml of dichloromethane. Evaporate the combined dichloromethane extracts to dryness with the aid of a current of warm air and use the residue as test substance 1.
• Withdraw and weigh an amount equivalent to 0.20 gm of lidocaine hydrochloride and use directly as test substance 2, dividing it into 3 equal parts.

Identity tests:

Procedures:

• To test substance 1, add 1 ml of ethanol (~750 gm/L) TS and 0.5 ml of cobalt (II) chloride (30 gm/L) TS and shake for 2, minutes; a bluish-green precipitate is produced.
• To 1 part of test substance 2 add 2 ml of water and 3 drops of iodine TS and mix; a brown precipitate is produced.
• Shake 2 parts of test substance 2 with 5 ml of water and add 1 ml of nitric acid (~130 gm/L) TS and 1 ml of silver nitrate (40 gm/L) TS; a white precipitate is produced. Separate the precipitate, wash it with water and add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

20. Magnesium Hydroxide Oral Suspension

Description: The suspension usually contains the equivalent of 55 mg of magnesium oxide in 1.0 ml of a suitable vehicle.

Preparation of the sample: Take a portion of the suspension equivalent to 0.20 gm of magnesium hydroxide and use it directly as the test solution, dividing it into 2 equal volumes.

Identity tests:

Procedures:

• To 1 volume of the test solution, add 5 ml of hydrochloric acid (~70 gm/L) TS and filter. To the filtrate add 5 ml of ammonium chloride (100 gm/L) TS, 3 ml of disodium hydrogen phosphate (100 gm/L) TS, and 5 ml of ammonia (-100 gm/L) TS; a white precipitate is produced which is soluble in acetic acid (~300 gm/L) TS.
• To 1 volume of the test, the solution adds 5 ml of hydrochloric acid (~70 gm/L) TS and 5 ml of sodium hydroxide (-80 gm/L) TS; a white, gelatinous precipitate is produced which is insoluble in an excess of sodium hydroxide (-80 gm/L) TS. Add a few drops of iodine TS; the color of the precipitate changes to dark brown.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

21. Magnesium Sulfate Powder

Description: Brilliant, colorless crystals or a white, crystalline powder, odorless. Preparation of the sample: Use the powder directly as the test substance.

Melting point: About 1124°C.

Identity tests:

Procedures:

• Dissolve 10 mg of the test substance in 2 ml of water and add 1 ml of ammonia (-100 gm/L) TS; a white precipitate is produced. Add 1 ml of ammonium chloride (100 gm/L) TS; the precipitate dissolves. Add 1 ml of disodium hydrogen phosphate (100 gm/L) TS; a white precipitate is produced.
• Dissolve 10 mg of the test substance in 2 ml of water and add 3 drops of titan yellow. TS and 2 ml of sodium hydroxide (~80 gm/L) TS; a distinct pink color is produced.
• Dissolve 0.05 gm of the test substance in 5 ml of water and add 1 ml of hydrochloric acid (~70 gm/L) TS and 1 ml of barium chloride (50 gm/L) TS; a white precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

22. Metoclopramide Hydrochloride Tablets

Description: Each tablet usually contains 10 mg of metoclopramide hydrochloride.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.35 gm of metoclopramide hydrochloride.
• Grind the tablets and weigh out the above-calculated equivalent amount as powdered material, shake it with 10 ml of water, and filter. Use the filtrate as the test. the solution, dividing it into 3 equal volumes. Melting point: About 147°C.

Identity tests:

Procedures:

• To 1 volume of the test solution, add 1 ml of hydrochloric acid (~70 gm/L) TS and 2 ml of sodium nitrite (10 gm/L) TS; a yellow color is produced.
• Mix 2 drops of potassium bromide (100 gm/L) TS with 4 drops of potassium bromate (15 gm/L) TS and dilute to 1 ml with water. Add 2 drops of sulfuric acid (-1760 gm/L) TS and 1 volume of the test solution; a yellowish precipitate is produced.
• To 1 volume of the test solution, add 1 ml of nitric acid (-130 gm/L) TS and 1 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash it with water and add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

23. Metronidazole Suppositories

Description: Each suppository usually contains 500 mg-1 gm of metronidazole.

Preparation of the sample: Dissolve a quantity of the suppository equivalent to 0.5 gm of metronidazole in 20 ml of hot water. Allow standing overnight to crystallize. Filter to separate the crystals, dry them at 105°C for about 3 hours, and use them as the test substance.

Description: A white or pale yellow, crystalline powder.

Melting point: About 161°C.

Identity tests:

Procedures:

• To 20 mg of the test substance, add 0.05 gm of 4-dimethylaminobenzaldehyde dissolved in 2 ml of hydrochloric acid (~70 gm/L) TS; the solution is almost colorless or has a yellow tint. Add 0.05 gm of zinc powder; a deep red color is produced.
• Boil 20 mg of the test substance with 5 ml of sodium hydroxide (~80 gm/L) TS; the solution shows the following colors in turn: pink, pink-violet, red-violet, red, red-brown, yellow-brown, and yellow.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

24. Miconazole Nitrate Cream

Description: The cream usually contains 20 mg of miconazole nitrate in 1.0 gm of a suitable cream base.

Preparation of the sample:

• Withdraw and weigh an amount equivalent to 0.10 gm of miconazole nitrate and use directly as the test substance, dividing it into 2 equal parts.
• Dissolve 1 part of the test substance in sufficient methanol to produce 50 ml, filter, and use as the test solution.

Melting point: About 170°C.

Identity tests:

Procedures:

• To 1 part of the test substance, add 2 ml of sodium hydroxide (-80 gm/L) TS and 20 gm of zinc powder. Boil gently; ammonia is produced which shows an alkaline range on moistened pH-indicator paper.
• Place 5 ml of the test solution in a porcelain crucible, add 0.1 gm of anhydrous sodium carbonate, evaporate to dryness over a water bath and ignite. Cool, dissolve the residue in 3 ml of nitric acid (-130 gm/L) TS, and add a few drops of silver nitrate (40 gm/L) TS; a white precipitate is produced. Separate the precipitate, wash with water and add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves.
• Cool 3 ml of the test solution in ice and add 0.4 ml of potassium chloride (100 gm/L) TS, 0.1 ml of diphenylamine/sulfuric acid TS and 10 ml of sulfuric acid (-1760 gm/L) TS; an intense blue color is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

25. Nystatin Ointment

Description: The ointment usually contains 100 000 IU of nystatin in 1.0 gm of a suitable ointment base.

Preparation of the sample: Withdraw and weigh an amount equivalent to 22,000 IU of nystatin, add 25 ml of dimethylformamide and shake well. Filter, evaporate the filtrate to dryness, and use the residue as the test substance.

Melting point: About 46°C.

Identity tests:

Procedures:

• To 5 mg of the test substance, add about 2 ml of sulfuric acid (~1760 gm/L) TS; a dark violet color is produced.
• To 5 mg of the test substance, add 1 ml of ethanol (~750 gm/L) TS and about 1 ml of hydrochloric acid (-250 gm/L) TS, shake and filter. To the filtrate, add a few crystals of resorcinol and heat in a water bath for 2 minutes; a pink color is produced.
• To 5 mg of the test substance, add 2 ml of ethanol (-750 gm/L) TS, shake and filter. To the filtrate, add about 1 ml of hydrochloric acid (-250 gm/L) TS and 2 drops of a solution composed of 1 ml of ferric chloride (25 gm/L) TS and 10 ml of water; a dark green color is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

26. Oral Rehydration Salts (Composition A)

Description: Each packet contains a white, crystalline powder composed of:

Table 1: Composition of ORS

Ingredients	Quantities
Glucose, anhydrous	20.0 gm
Sodium chloride	3.5 gm
Sodium hydrogen carbonate	2.5 gm
Potassium chloride	1.5 gm

Preparation of the sample:

• Weigh the contents of 1 packet; it should weigh between 26.0 gm and 29.0 gm.
• Use the contents of 1 packet directly as the test substance.
• Dissolve the contents of 1 packet in 250 ml of water and use as the test solution.

Identity tests:

Melting behavior: Gently heat a small quantity of the test substance; after melting it first changes to yellow and then to brown and an odor of burning sugar is perceptible. Then ignite; the melt swells ignite and chars.

Procedures:

• The test solution is slightly alkaline when tested with pH-indicator paper.
• Add a few drops of the test solution to 5 ml of hot potassio-cupric tartrate TS; a copious red precipitate is produced (glucose).
• Acidify 5 ml of the test solution with acetic acid (-300 gm/L) TS, add 2 ml of magnesium uranyl acetate TS and scratch the sides of the beaker with a glass rod; a light yellow, crystalline precipitate is slowly produced (sodium).
• Alternative test: Introduce the test solution into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color (sodium).
• To 5 ml of the test solution, add 0.5 ml of nitric acid (-130 gm/L) TS and 0.5 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash with water and add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves (chlorides).
• To 5 ml of the test solution, add 2 drops of phenolphthalein/ethanol TS; a pink color is produced. Heat to boiling; a gas is evolved and the color of the solution changes to red-violet (hydrogen carbonate).
• To 5 ml of the test solution, add 1 ml of acetic acid (-60 gm/L) TS and 4 drops of sodium cobaltinitrite (100 gm/L) TS; a yellow-orange precipitate is produced (potassium).

Degradation test: Discoloration of the test solution usually indicates gross degradation,

27. Oral Rehydration Salts (Composition B)

Description: Each packet contains a white, crystalline powder composed of:

Table 2: Composition of ORS

Ingredients	Quantities
Glucose, anhydrous	20.0 gm
Sodium chloride	3.5 gm
Sodium citrate dihydrate	2.9 gm
Potassium chloride	1.5 gm

Preparation of the sample:

• Weigh the contents of 1 packet; it should weigh between 26.0 gm and 29.0 gm.
• Use the contents of 1 packet directly as the test substance.
• Dissolve the contents of 1 packet in 250 ml of water and use it as the test solution.

Identity test:

Melting behavior: Gently heat a small quantity of the test substance; after melting it first changes to yellow and then to brown and an odor of burning sugar is perceptible. Then ignite; the melt swells ignite and chars.

Procedures:

• The test solution is slightly alkaline when tested with pH-indicator paper.
• Add a few drops of the test solution to 5 ml of hot potassio-cupric tartrate TS; a copious red precipitate is produced (glucose).
• Acidify 5 ml of the test solution with acetic acid (~300 gm/L) TS, add 2 ml of magnesium uranyl acetate TS and scratch the sides of the beaker with a glass rod; a light yellow, crystalline precipitate is slowly produced (sodium).
• Alternative test: Introduce the test solution into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color (sodium).
• To 5 ml of the test solution, add 0.5 ml of nitric acid (~130 gm/L) TS and 0.5 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash with water and add an excess of ammonia (~100 gm/L) TS; the precipitate dissolves (chlorides).
• To 5 ml of the test solution, add 3 ml of calcium chloride (55 gm/L) TS; no precipitate is produced. Boil the solution; a white solid is produced which is soluble in acetic acid (-300 gm/L) TS (citrates).
• To 5 ml of the test solution, add 1 ml of acetic acid (-60 gm/L) TS and 4 drops of sodium cobaltinitrite (100 gm/L) TS; a yellow-orange precipitate is produced (potassium).

Degradation test: Discoloration of the test solution usually indicates gross degradation.

28. Paracetamol Suppositories

Description: Each suppository usually contains 100 mg of Paracetamol.

Preparation of the sample:

• Weigh 1 suppository and calculate the amount equivalent to 0.5 gm of Paracetamol. Dissolve a quantity of the suppositories equivalent to 0.5 gm of Paracetamol in 25 ml of light petroleum by warming carefully over a water bath. Collect the residue by decanting, wash with 3 portions of 25 ml of light petroleum, and use as the test substance.

Identity tests:

Description: A white, crystalline powder.

Melting point: About 170°C.

The eutectic temperature of the test substance: With benzamide about 137°C with phenacetin, about 114°C.

Procedures:

• Dissolve 0.10 gm of the test substance in 10 ml of water and add 1 drop of ferric chloride (-25 gm/L) TS; an intense violet-blue color is produced.
• To 0.10 gm of the test substance, add 1 ml of hydrochloric acid (-70 gm/L) TS and boil for 1 minute. Add 10 ml of water and cool; no precipitate is produced. Add 1 drop of potassium dichromate (100 gm/L) TS and shake; a violet color slowly develops and does not change to red (distinction from phenacetin).

Degradation test: Discoloration of the test solution usually indicates gross degradation.

29. Phenytoin Tablets

Description: Each tablet usually contains 50 mg of phenytoin.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.08 gm of phenytoin.
• Grind the tablets, weigh out the above-calculated equivalent amount as a powdered material and use it directly as the test substance, dividing it into 2 equal parts.

Melting point: About 298°C.

Identity tests:

Procedures:

• To 1 part of the test substance, add 4 ml of ethanol (~750 gm/L) TS, shake and filter. To the filtrate, add 4 drops of cobalt (II) chloride (30 gm/L) TS and 1 drop of ammonia (~260 gm/L) TS; a blue-violet color is produced.
• To half of 1 part of the test substance placed on a white test plate add 2 drops of ammonia (-100 gm/L) TS and 1 small drop of copper (II) sulfate (160 gm/L) TS and mix thoroughly with a glass rod; a pink precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

30. Phenytoin Sodium Capsules

Description: Each capsule usually contains 25-100 mg of phenytoin sodium.

Preparation of the sample:

• Weigh the contents of 1 capsule and calculate the amount equivalent to 0.08 gm of phenytoin sodium.
• Empty the capsules, weigh out the above-calculated equivalent amount and use it directly as the test substance, dividing it into 4 equal parts.

Melting point: About 298°C.

Identity tests:

Procedures:

• To 2 parts of the test substance, add 4 ml of dichloromethane and 4 drops of cobalt (II) chloride (30 gm/L) TS and shake; a voluminous precipitate is produced in a blue-violet colored solution (distinction from phenytoin).
• Place half of 1 part of the test substance on a white test plate, add 2 drops of ammonia (-100 gm/L) TS and 1 small drop of copper (II) sulfate (160 gm/L) TS and mix thoroughly with a glass rod; a pink precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

31. Phytomenadione Injection

Description: The injection is a sterile solution usually containing 10 mg of phytomenadione in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 20 mg of phytomenadione; if necessary, reduce the volume by evaporation to about 2 ml or dilute to about 2 ml with water. Use directly as the test solution.

Identity tests:

Procedures:

• Dilute about 1 ml of the test solution with 10 ml of ethanol (~750 gm/L) TS and add 3 ml of potassium hydroxide/ethanol TS; a green color is produced. Allow to stand for 1-2 minutes; the color changes to blue. Again allow standing for about 15 minutes; the color changes to red-brown.
• To about 1 ml of sulfuric acid (-1760 gm/L) TS, add 3 drops of the test solution; a brown-orange color is produced. Heat the solution; the color changes to dark brown.
• To 3 drops of the test solution, add 5 ml of ethanol (-750 gm/L) TS and 2-5 drops of potassium permanganate (10 gm/L) TS and shake; the color of the permanganate is immediately discharged.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

32. Piperazine Citrate Syrup

Description: The syrup contains piperazine citrate, usually equivalent to 500 mg of piperazine hydrate in 5 ml of a suitable vehicle.

Preparation of the sample: Use the well-homogenized contents of one container or the equivalent of 0.5 gm of piperazine hydrate and use directly as the test solution, dividing it into 3 equal volumes.

Identity tests:

Procedures:

• To 2 volumes of the test solution, add 5 ml of hydrochloric acid (-70 gm/L) TS and then add while stirring 1 ml of sodium nitrite (500 gm/L) TS. Cool in ice for 15 minutes, stirring if necessary to induce crystallization. Filter, wash the crystals with 10 ml of ice water, and dry at 105°C melting point, about 158°C.
• To 1 volume of the test solution, add 3 ml of calcium chloride (55 gm/L) TS; no precipitate is produced. Boil the solution; a white solid is produced which is soluble in acetic acid (-300 gm/L) TS.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

33. Potassium Chloride Solution

Description: The solution usually contains 112 mg of potassium chloride in 1.0 ml of a suitable vehicle.

Preparation of the sample:

• Pool the contents of the containers equivalent to 0.30 gm of potassium chloride and use directly as test solution 1.
• Dilute 1.0 ml of test solution 1 with sufficient water to produce 10 ml and use as test solution 2.

Identity tests:

Procedures:

• Introduce test solution 1, together with hydrochloric acid (-250 gm/L) TS, into a non-luminous flame using a magnesia stick or a nichrome or a platinum wire sealed to a glass rod; the flame acquires a violet color which, when viewed through a suitable blue glass, appears reddish violet.
• To 1.0 ml of test solution 2, add 3 ml of water and 5 drops of silver nitrate (40 gm/L) TS: a white, curdy precipitate is produced. Separate the precipitate, wash with water and add a few drops of ammonia (-100 gm/L) TS; the precipitate dissolves.
• Heat 2-3 drops of test solution 1 with a few drops of sodium hydroxide (-80 gm/L) TS; no odor of ammonia is perceptible.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

34. Pyrimethamine Tablets

Description: Each tablet usually contains 25 mg of pyrimethamine.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.25 gm of pyrimethamine.
• Grind the tablets, weigh out the above-calculated equivalent amount as powdered material, shake it with 50 ml of ethanol (-750 gm/L) TS heated to 60°C filters, and evaporate to dryness. Dry the residue to constant weight at 105°C and use it as the test substance.

Identity tests:

Melting point: The test substance melts at about 239°C.

Procedures:

• Dissolve 0.05 gm of the test substance in 5 ml of sulfuric acid (-100 gm/L) TS and add 0.2 ml of freshly prepared potassio-mercuric iodide TS; a creamy white precipitate is produced.
• To 1 ml of methyl orange/ethanol TS, add 5 ml of water and 2 ml of ethyl acetate and shake; the ethyl acetate layer remains colorless. Add a solution of 5 mg of the test substance dissolved in 5 ml of sulfuric acid (~5 gm/L) TS, shake and allow to separate (about 30 minutes); a yellow color is produced in the ethyl acetate layer.
• Ignite about 0.1 gm of the test substance with 0.5 gm of anhydrous sodium carbonate, cool, add 5 ml of hot water, and heat in a water bath for 5 minutes. Filter, neutralize the filtrate with nitric acid (-130 gm/L) TS, and add 5 drops of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

35. Reserpine Injection

Description: The injection is a sterile solution usually containing 1 mg of reserpine in 10 ml of a suitable vehicle. Preparation of the sample: Pool the contents of the ampoules equivalent to 2.0 mg of reserpine and use directly as the test solution, dividing it into 4 equal volumes.

Identity tests:

Procedures:

• To 1 volume of the test solution, add 1 ml of dichloromethane, shake and allow to stand. Separate the dichloromethane layer and evaporate it to dryness over a water bath. Mix the residue with 5 mg of 4-dimethylaminobenzaldehyde and 4 drops of glacial acetic acid. Then add 4 drops of sulfuric acid (-1760 gm/L) TS; a green color is produced. Add about 1 ml of glacial acetic acid; the color changes to red.
• To 2 volumes of the test solution, add 1 drop of sulfuric acid (-100 gm/L) TS and a few drops of sodium nitrite (10 gm/L) TS; a yellowish-green solution is produced which exhibits a greenish fluorescence.
• To 1 volume of the test solution, add a few drops of ammonium vanadate (5 gm/L) TS; a green color is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation,

36. Sodium Chloride Injection

Description: The injection is a sterile solution usually containing 9 mg of sodium chloride in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the containers equivalent to about 30 mg of sodium chloride; if necessary, reduce the volume by evaporation to about 3 ml c dilute to about 3 ml with water. Use directly as the test solution.

Identity tests:

Procedures:

• Introduce a few drops of the test solution into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color.
• To 2 ml of the test solution, add 3 drops of nitric acid (~130 gm/L) TS and 3 drops of silver nitrate (40 gm/L) TS and shake; a white, curdy precipitate is produced. Separate the precipitate, wash with water and add an excess of ammonia (~100 gm/L) TS; the precipitate dissolves.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

37. Sodium Hydrogen Carbonate Injection

Description: The injection is a sterile solution usually containing 14 mg of sodium hydrogen carbonate in 1.0 ml of a suitable vehicle. Preparation of the sample: Pool the contents of the ampoules equivalent to 0.30 gm o sodium hydrogen carbonate and use directly as the test solution, dividing it into 3 equal volumes.

Identity tests:

Procedures:

• Introduce a few drops of the test solution into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color.
• Dilute 1 volume of the test solution with 3 ml of water and add 2 drops d phenolphthalein/ethanol TS; a pink color is produced. Heat to boiling; a colorless and odorless gas evolves and the color of the solution changes to red-violet.
• Dilute 1 volume of the test solution with 3 ml of water and add a few drops d magnesium sulfate (50 gm/L) TS; no precipitate is produced. Boil the mixture: a white precipitate is produced.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

38. Sodium Lactate Injection

Description: The injection is a sterile solution usually containing 500 mg of monosodium lactate in 1.0 ml of a suitable vehicle.

Preparation of the sample: Dilute a volume of the solution equivalent to 0.5 gm of sodium lactate to 5 ml with water and use it directly as the test solution.

Identity tests:

Procedures:

• To 0.5 ml of the test solution, add 2 ml of sulfuric acid (-100 gm/L) TS and 3 ml of potassium permanganate (10 gm/L) TS; the color of the permanganate is discharged and an odor of acetaldehyde is perceptible.
• To 1 ml of the test solution, add 4 ml of water and mix. Add 1 ml of acetic acid (~300 gm/L) TS and 1 ml of ammonium oxalate (25 gm/L) TS; no precipitate is produced (distinction from calcium lactate).
• To a few drops of the test solution, add a small volume of hydrochloric acid (-250 gm/L) TS and introduce the mixture into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color.
• Alternative test: To 5 drops of the test solution, add 1 ml of water, acidify with acetic acid (-300 gm/L) TS and add 2 ml of magnesium uranyl acetate TS; a light yellow, crystalline precipitate is produced.
• To 2 ml of the test solution, add along the wall of the test tube, 5 ml of a reagent composed of 0.10 gm of catechol dissolved in 10 ml of sulfuric acid (-1760 gm/L) TS; a deep red color is produced at the junction of the two liquids.

39. Verapamil Hydrochloride Injection

Description: The injection is a sterile solution usually containing 2.5 mg of verapamil hydrochloride in 1.0 ml of a suitable vehicle.

Preparation of the sample: Pool the contents of the ampoules equivalent to 15 mg of verapamil hydrochloride and use directly as the test solution, dividing it into 3 equal volumes.

Identity tests:

Procedures:

• To 1 volume of the test solution, add about 0.2 ml of mercuric chloride (65 gm/L) TS; a white precipitate is produced.
• To 1 volume of the test solution, add 0.5 ml of sulfuric acid (-100 gm/L) TS and 4 drops of potassium permanganate (10 gm/L) TS; a violet precipitate is produced which immediately dissolves to produce a very pale yellow solution.
• Acidify 1 volume of the test solution with nitric acid (-130 gm/L) TS and add 2 ml of silver nitrate (40 gm/L) TS; a white, curdy precipitate is produced. Separate the precipitate, wash with water and add an excess of ammonia (-100 gm/L) TS; the precipitate dissolves

Degradation test: Discoloration and a change in the physical state of the test solution usually indicate gross degradation.

40. Warfarin Sodium Tablets

Description: Each tablet usually contains 1-5 mg of warfarin sodium.

Preparation of the sample:

• Weigh 1 tablet and calculate the amount equivalent to 0.10 gm of warfarin sodium.
• Grind the tablets, weigh out the above-calculated equivalent amount as powdered material.
• Extract the powdered material with two quantities, each of 15 ml, of water. Filter and to the filtrate add 2 drops of hydrochloric acid (-70 gm/L) TS. Filter, wash the precipitate with water, and dry at 110°C for 3 hours; melting point, about 162°C. Use the crystals as the test substance.

Identity tests:

Procedures:

• Dissolve 20 mg in 1 ml of water and add 5 drops of sodium hydroxide (-80 gm/L) TS and 5 drops of iodine TS; a yellow precipitate is produced and a characteristic odor of iodoform is perceptible.
• Moisten 10 mg with 1 drop of hydrochloric acid (~70 gm/L) TS and introduce the mixture into a non-luminous flame using a magnesia stick or a nichrome or platinum wire sealed to a glass rod; the flame acquires an intense yellow color.

Degradation test: Discoloration of the test solution usually indicates gross degradation.

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