Trifluoperazine Hydrochloride Syrup (Current title—not to change until June 1,2005) Monograph title change—to become official June 1,2005 See Trifluoperazine Oral Solution »Trifluoperazine Hydrochloride Syrup contains an amount of trifluoperazine hydrochloride (C21H24F3N3S·2HCl)equivalent to not less than 93.0percent and not more than 107.0percent of the labeled amount of trifluoperazine (C21H24F3N3S). Packaging and storage— Preserve in tight,light-resistant containers. USP Reference standards á11ñ USP Trifluoperazine Hydrochloride RS. NOTE—Throughout the following procedures,protect test or assay specimens,the Reference Standard,and solutions containing them,by conducting the procedures without delay,under subdued light,or using low-actinic glassware. Identification— A: The UVabsorption spectrum of the solution employed for measurement of absorbance in the Assayexhibits maxima and minima at the same wavelengths as that of a similar solution of USP Trifluoperazine Hydrochloride RS,concomitantly measured. B: Mix 1mLof Syrup with 5mLof methanol:a 5-µLportion of this solution responds to Identificationtest Dunder Trifluoperazine Hydrochloride. pHá791ñ: between 2.0and 3.2. Assay— [NOTE—Use low-actinic glassware.]Transfer an accurately measured volume of Syrup,equivalent to about 50mg of trifluoperazine,to a 250-mLseparator with the aid of about 100mLof water.Add 10mLof sodium hydroxide solution (1in 10),and extract with three 50-mLportions of cyclohexane.Wash the combined cyclohexane extracts with about 20mLof water,and discard the water washing.Extract the combined cyclohexane extracts with four 50-mLportions of 0.1Nhydrochloric acid,collecting the aqueous extracts in a 500-mLvolumetric flask.Dilute with 0.1Nhydrochloric acid to volume,and mix.Transfer 10.0mLof this solution to a 100-mLvolumetric flask,dilute with 0.1Nhydrochloric acid to volume,and mix.Concomitantly determine the absorbances of this solution and of a Standard solution of USP Trifluoperazine Hydrochloride RSin the same medium having a known concentration of about 12µg per mLin 1-cm cells at 278nm and at the wavelength of maximum absorbance at about 255nm,with a suitable spectrophotometer,using 0.1Nhydrochloric acid as the blank.Calculate the quantity,in mg,of trifluoperazine (C21H24F3N3S)in each mLof the Syrup taken by the formula: (407.51/480.43)(5C/V)(A255-A278)U/(A255-A278)S, in which 407.51and 480.43are the molecular weights of trifluoperazine and trifluoperazine hydrochloride,respectively;Cis the concentration,in µg per mL,of USP Trifluoperazine Hydrochloride RSin the Standard solution;Vis the volume,in mL,of Syrup taken;and the parenthetic expressions are the differences in the absorbances of the two solutions at the wavelengths indicated by the subscripts,for the assay solution (U)and the Standard solution (S),respectively. Auxiliary Information— Staff Liaison:Ravi Ravichandran,Ph.D.,Senior Scientist Expert Committee:(PA3)Pharmaceutical Analysis 3 USP28–NF23Page 1976 Pharmacopeial Forum:Volume No.28(2)Page 385 Phone Number:1-301-816-8330