C11H17N2NaO3 248.25

2,4,6(1H,3H,5H)-Pyrimidinetrione, 5-ethyl-5-(3-methylbutyl)-, monosodium salt.
Sodium 5-ethyl-5-isopentylbarbiturate [64-43-7].

Packaging and storage— Preserve in tight containers.

Labeling— Where it is intended for use in preparing injectable dosage forms, the label states that it is sterile or must be subjected to further processing during the preparation of injectable dosage forms.

USP Reference standards 11— USP Amobarbital RS. USP Endotoxin RS.

Completeness of solution 641— Mix 1.0 g with 10 mL of carbon dioxide-free water: after 1 minute, the solution is clear and free from undissolved solid.

Identification—

pH 791: not more than 11.0, in the solution prepared for the test for Completeness of solution.

Loss on drying 731— Dry about 1 g, accurately weighed, at 105 for 4 hours: it loses not more than 2.0% of its weight.

Heavy metals, Method II 231: 0.003%.

Organic volatile impurities, Method I 467: meets the requirements.

Residual solvents 467: meets the requirements.

Other requirements— Where the label states that Amobarbital Sodium is sterile, it meets the requirements for Sterility and Bacterial endotoxins under Amobarbital Sodium for Injection. Where the label states that Amobarbital Sodium must be subjected to further processing during the preparation of injectable dosage forms, it meets the requirements for Bacterial endotoxins under Amobarbital Sodium for Injection.

Assay— Dissolve about 500 mg of Amobarbital Sodium, accurately weighed, in about 15 mL of water in a separator. To the solution add 2 mL of hydrochloric acid, shake, and completely extract the liberated amobarbital with 25-mL portions of chloroform. Test for completeness of extraction by extracting with an additional 10-mL portion of chloroform and evaporating the solvent: not more than 0.5 mg of residue remains. Filter the combined extract through a glass filter funnel into a tared beaker, and wash the separator and the filter with several small portions of chloroform. Evaporate the combined filtrate and washings on a steam bath with the aid of a current of air, dry the residue at 105 for 30 minutes, cool, and weigh. The weight of the residue, multiplied by 1.097, represents the weight of C11H17N2NaO3.

Expert Committee : (MDPP05) Monograph Development-Psychiatrics and Psychoactives

USP29–NF24 Page 153

Phone Number : 1-301-816-8330