Oxazepam Tablets
»Oxazepam Tablets contain not less than 90.0percent and not more than 110.0percent of the labeled amount of C15H11ClN2O2.
Packaging and storage— Preserve in well-closed containers.
Identification— The solution prepared for measurement of absorbance in the Assayexhibits a maximum at 229±2nm.
Dissolution á711ñ—
Medium: 0.1Nhydrochloric acid;1000mL.
Apparatus 2: 50rpm.
Time: 60minutes.
Chromatographic system— The liquid chromatograph is fitted with a 232-nm detector and a 4-mm ×30-cm column that contains packing L7.The mobile phase is a degassed mixture of methanol,water,and glacial acetic acid (60:40:1),and the flow rate is about 2mLper minute.In a suitable system,the relative standard deviation observed following replicate injections is not more than 3.0%.
Procedure— Inject an accurately measured volume (about 10µL)of a filtered portion of the solution under test into the chromatograph by means of a microsyringe or a sampling valve,record the chromatogram,and measure the response for the major peak.Calculate the quantity of C15H11ClN2O2dissolved in comparison with a similarly chromatographed Standard solution having a known concentration of USP Oxazepam RSin 0.1Nhydrochloric acid.[NOTE—Avolume of alcohol not exceeding 10%of the final total volume of the Standard solution may be used to dissolve the Reference Standard.]
Tolerances— Not less than 80%(Q)of the labeled amount of C15H11ClN2O2is dissolved in 60minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Assay— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 50mg of oxazepam,to a medium-porosity,sintered-glass funnel that is fitted into a small suction flask,and proceed as directed in the Assayunder Oxazepam Capsules,beginning with “Add 25mLof alcohol.”Calculate the quantity,in mg,of C15H11ClN2O2in the portion of Tablets taken by the formula:
12.5C(AU/AS),
in which Cis the concentration,in µg per mL,of USP Oxazepam RSin the Standard solution,and AUand ASare the absorbances of the solution from the Tablets and the Standard solution,respectively.
Auxiliary Information— Staff Liaison:Ravi Ravichandran,Ph.D.,Senior Scientist
Expert Committee:(PA3)Pharmaceutical Analysis 3
USP28–NF23Page 1429
Phone Number:1-301-816-8330