Temazepam Capsules »Temazepam Capsules contain not less than 90.0percent and not more than 110.0percent of the labeled amount of temazepam (C16H13O2N2Cl). Caution—Temazepam is a potent sedative:its powder should not be inhaled. Packaging and storage— Preserve in well-closed,light-resistant containers. USP Reference standards á11ñ USP Temazepam RS. Identification— A: The retention time of the major peak in the chromatogram of the Assay preparationcorresponds to that of the Standard preparation,both relative to the internal standard,as obtained in the Assay. B: Transfer a portion of the Capsule contents,equivalent to about 50mg of temazepam,to a 25-mLvolumetric flask,add 10mLof methanol,shake by mechanical means,and allow to settle.Use the supernatant layer as the test solution.Separately apply 20µLof the test solution and 20µLof a Standard solution of USP Temazepam RSin methanol containing 5.0mg per mLto a thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture.Place the plate in a chromatographic chamber,and develop the chromatogram in a solvent system consisting of a mixture of toluene,dioxane,methanol,and ammonium hydroxide (65:30:5:1)until the solvent front has moved about three-fourths of the length of the plate.Remove the plate from the developing chamber,mark the solvent front,air-dry,and examine the plate under short-wavelength UVlight:the RFvalue of the principal spot obtained from the test solution corresponds to that obtained from the Standard solution. Dissolution á711ñ Sodium acetate buffer— Dissolve 2g of sodium hydroxide in 450mLof water in a 1-liter volumetric flask.Adjust with acetic acid to a pHof 4.0,dilute with water to volume,mix,and deaerate. Medium: Sodium acetate bufferwith 0.05%polysorbate 80;900mL. Apparatus 2: 75rpm. Time: 30minutes. Determine the amount of C16H13O2N2Cl dissolved from UVabsorbances,at the wavelength of maximum absorbance at about 310nm of filtered portions of the solution under test,suitably diluted with Sodium acetate buffer,in comparison with a Standard solution having a known concentration of USP Temazepam RSin the same medium. Tolerances— Not less than 80%(Q)of the labeled amount of C16H13O2N2Cl is dissolved in 30minutes. Uniformity of dosage units á905ñ: meet the requirements. Assay— Buffer solution,Mobile phase,Internal standard solution,Standard preparation,Chromatographic system,and Procedure Proceed as directed in the Assayunder Temazepam. Assay preparation— Weigh the contents of not less than 20Capsules,and calculate the average weight per Capsule.Mix the combined contents,and transfer an accurately weighed portion of the Capsule contents,equivalent to about 40mg of temazepam,to a 200-mLvolumetric flask,add 150mLof Internal standard solution,and shake the mixture by mechanical means for 30minutes.Dilute with Internal standard solutionto volume,and mix.Allow the contents of the flask to settle,and filter,discarding the first 5mLof the filtrate. Auxiliary Information— Staff Liaison:Salvador C.Salado,M.S.,Scientist and Latin American Liaison Expert Committee:(PA3)Pharmaceutical Analysis 3 USP28–NF23Page 1866 Phone Number:1-301-816-8165