Procedure for content uniformity
Transfer 1 Tablet to a 100-mL volumetric flask, add 70 mL of water, and sonicate, swirling the flask intermittently, until the tablet is dissolved. Dilute with water to volume, mix, and filter, discarding the first 50 mL of the filtrate. Dilute a portion of the filtrate quantitatively and stepwise with 0.1 N sulfuric acid to obtain a solution having a concentration of about 1.25 µg of triprolidine hydrochloride per mL. Concomitantly determine the fluorescence intensities of this solution and a similarly prepared Standard solution having a known concentration of about 1.25 µg of
USP Triprolidine Hydrochloride RS per mL, at the excitation wavelength of 300 nm with a slit width of 2 mm, and an emission wavelength of 460 nm with a slit width of 2 mm, with a suitable spectrophotometer, using 0.1 N sulfuric acid as the blank. Calculate the quantity, in mg, of C
19H
22N
2·HCl·H
2O in the Tablet taken by the formula:
(332.88/314.86)(TC/D)(IU / IS),
in which 332.88 and 314.86 are the molecular weights of the monohydrate and anhydrous forms of triprolidine hydrochloride, respectively;
T is the labeled quantity, in mg, of triprolidine hydrochloride in the Tablet;
C is the concentration, in µg per mL, of
USP Triprolidine Hydrochloride RS in the Standard solution;
D is the concentration, in µg per mL, of triprolidine hydrochloride in the solution from the Tablet, on the basis of the labeled quantity per Tablet and the extent of dilution, and
IU and
IS are the fluorescence intensities of the solution from the Tablet and the Standard solution, respectively.