Identification
Dilute 1mLwith methanol to 5mL.Apply 5µLeach of this solution and a solution of
USP Perphenazine RSin methanol containing 1mg per mLto a suitable thin-layer chromatographic plate,coated with a 0.25-mm layer of chromatographic silica gel.Develop the chromatogram in a solvent system consisting of a mixture of acetone and ammonium hydroxide (200:1)until the solvent front has moved about 15cm.Air-dry the plate,and spray lightly with a solution of iodoplatinic acid prepared by dissolving 100mg of chloroplatinic acid in 1mLof 1Nhydrochloric acid,adding 25mLof potassium iodide solution (4in 100),diluting with water to 100mL,and adding 0.50mLof formic acid:the
RFvalue of the principal spot obtained from the Injection corresponds to that obtained from the Standard solution.
Assay
Acid-alcohol solution
Transfer 10mLof hydrochloric acid to a 1000-mLflask containing 500mLof alcohol and 300mLof water.Dilute with water to volume.
Palladium chloride solution
Dissolve 100mg of palladium chloride in a mixture of 1mLof hydrochloric acid and 50mLof water in a 100-mLvolumetric flask,heating on a steam bath to effect solution.Cool,dilute with water to volume,and mix.Store in an amber bottle and use within 30days.On the day of use,transfer 50mLto a 500-mLvolumetric flask,add 4mLof hydrochloric acid and 4.1g of anhydrous sodium acetate,dilute with water to volume,and mix.
Standard preparation
Dissolve an accurately weighed quantity of
USP Perphenazine RSin
Acid-alcohol solutionto obtain a solution having a known concentration of about 150µg per mL.
Assay preparation
Dilute 3.0mLof Injection with Acid-alcohol solutionto 100mLin a volumetric flask.
Procedure
Mix 10.0mLeach of the
Assay preparationand the
Standard preparationwith 15.0mLof
Palladium chloride solution,filter,if necessary,and concomitantly determine the absorbances of these solutions,against a reagent blank,in 1-cm cells at the wavelength of maximum absorbance at about 480nm,with a suitable spectrophotometer.Calculate the quantity,in mg,of C
21H
26ClN
3OSin the volume of Injection taken by the formula:
0.1C(AU/AS),
in which
Cis the concentration,in µg per mL,of
USP Perphenazine RSin the
Standard preparation,and
AUand
ASare the absorbances of the solutions from the
Assay preparationand the
Standard preparation,respectively.