Assay of Phenobarbitone: Medicinal Chemistry Practical

Assay of Phenobarbitone: Medicinal Chemistry Practical

BP406P Medicinal Chemistry I Practical

AIM :

To perform the Assay of Phenobarbitone.

REFERENCE:

1. A textbook of Medicinal Chemistry-I, Pragi Arora, Varun Arora, Davinder Kumar, Page no:282,283.
2. Indian Pharmacopoeia Volume III  2018,Page No:2899,2900.

REQUIREMENTS:

Sodium hydroxide, aldehyde free ethanol, benzoic acid, thymolphthalein solution,

silver nitrate, pyridine and ether, conical flask, burette, beaker, pipette etc.

PRINCIPILE:

Phenobarbitone is assayed by non-aqueous titration. In this method, the drug is dissolved in the pyridine and titrated with sodium hydroxide solution using thymolphthalein as an indicator.

PROCEDURE:

1. STANDARDISATION OF SODIUM HYDROXIDE SOLUTION

Actually weighed  0.6g of benzoic acid and dissolved it in a mixture of 30ml of ethanol and 6ml of water and titrated with ethanolic sodium hydroxide solution using 0.2ml of thymolphthalein as an indicator.

ASSAY OF PHENOBARBITONE

Weighed and powdered  20 tablets. Weighed a quantity of the powder containing about 0.1g (100 mg ) of phenobarbitone in 5ml of pyridine add 0.25 ml of thymolphthalein solution and 10 ml of silver nitrate pyridine reagent and titrated with 0.1M ethanolic sodium hydroxide until the purely blue colour is obtained. Repeated the operation without the substance under examination.

The difference between the titrations represents the amount of sodium hydroxide required.

Equivalent factor: 1ml of 0.1M ethanolic sodium hydroxide=0.01161g of C12H12N2O3

REPORT

The percentage purity of Phenobarbitone was found to be =

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Second Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise

S Y B Pharm Sem III	S Y B Pharm Sem IV
BP301T Pharmaceutical Organic Chemistry II Theory	BP401T Pharmaceutical Organic Chemistry III Theory
BP302T Physical Pharmaceutics I Theory	BP402T Medicinal Chemistry I Theory
BP303T Pharmaceutical Microbiology Theo	BP403T Physical Pharmaceutics II Theory
BP304T Pharmaceutical Engineering Theory	BP404T Pharmacology I Theory
BP305P Pharmaceutical Organic Chemistry II Practical	BP405T Pharmacognosy I Theory
BP306P Physical Pharmaceutics I Practical	BP406P Medicinal Chemistry I Practical
BP307P Pharmaceutical Microbiology Practical	BP407P Physical Pharmaceutics II Practical
BP308P Pharmaceutical Engineering Practical	BP408P Pharmacology I Practical
	BP409P Pharmacognosy I Practical

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Suggested readings

• Study effect of hepatic microsomal enzyme inducers on phenobarbitone
• BP406P Medicinal Chemistry I Practical
• Preparation and standardization of Sodium hydroxide Standard solution
• BP607P Medicinal Chemistry III Practical
• Assay of Ammonium chloride Pharmaceutical Analysis I Practical

Recommended readings:

• Pharmaceutics I Practical
• Pharmaceutical Analysis I Theory