Amobarbital Sodium
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].
»Amobarbital Sodium contains not less than 98.5percent and not more than 100.5percent of C11H17N2NaO3,calculated on the dried basis.
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.
Completeness of solution á641ñ—
Mix 1.0g with 10mLof carbon dioxide-free water:after 1minute,the solution is clear and free from undissolved solid.
Identification—
A:
Infrared Absorption á197Kñ:of residue obtained in the Assay.
B:
Ignite about 200mg:the residue effervesces with acid and responds to the tests for Sodium á191ñ.
pHá791ñ:
not more than 11.0,in the solution prepared for the test for Completeness of solution.
Loss on drying á731ñ—
Dry about 1g,accurately weighed,at 105
for 4hours:it loses not more than 2.0%of its weight.
for 4hours:it loses not more than 2.0%of its weight.
Heavy metals,Method IIá231ñ:
0.003%.
Organic volatile impurities,Method Iá467ñ:
meets the requirements.
Other requirements—
Where the label states that Amobarbital Sodium is sterile,it meets the requirements for Sterilityand Bacterial endotoxinsunder 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 endotoxinsunder Amobarbital Sodium for Injection.
Assay—
Dissolve about 500mg of Amobarbital Sodium,accurately weighed,in about 15mLof water in a separator.To the solution add 2mLof hydrochloric acid,shake,and completely extract the liberated amobarbital with 25-mLportions of chloroform.Test for completeness of extraction by extracting with an additional 10-mLportion of chloroform and evaporating the solvent:not more than 0.5mg 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 105for 30minutes,cool,and weigh.The weight of the residue,multiplied by 1.097,represents the weight of C11H17N2NaO3.
for 30minutes,cool,and weigh.The weight of the residue,multiplied by 1.097,represents the weight of C11H17N2NaO3.
Auxiliary Information—
Staff Liaison:Ravi Ravichandran,Ph.D.,Senior Scientist
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 140
Pharmacopeial Forum:Volume No.29(6)Page 1845
Phone Number:1-301-816-8330