A: Weigh and finely powder not less than 20Tablets.Transfer a portion of the powder,equivalent to about 20mg of triprolidine hydrochloride,to a glass-stoppered test tube,add 20mLof water,and shake for 3minutes.Add 2mLof 1Nsodium hydroxide,mix,then add 3mLof cyclohexane,shake for 3minutes,and centrifuge for 5minutes:the IRabsorption spectrum of the clear supernatant so obtained exhibits maxima only at the same wavelengths as that of a similar preparation of USP Triprolidine Hydrochloride RS.

B: The retention time of the major peak in the chromatogram of theAssay preparation corresponds to that in the chromatogram of theStandard preparation as obtained in theAssay.

Medium: pH4.0±0.05acetate buffer,prepared by mixing 4.9g of glacial acetic acid and 2.45g of sodium acetate trihydrate with water to obtain 1000mLof solution;500mL.

Apparatus 1: 50rpm.

Time: 30minutes.

Procedure— Determine the amount of C19H22N2·HCl·H2Odissolved from UVabsorbances at the wavelength of maximum absorbance at about 277nm of filtered portions of the solution under test,in comparison with a Standard solution having a known concentration of USP Triprolidine Hydrochloride RSin the same medium.

Tolerances— Not less than 80%(Q)of the labeled amount of C19H22N2·HCl·H2Ois dissolved in 30minutes.

Procedure for content uniformity— Transfer 1Tablet to a 100-mLvolumetric flask,add 70mLof water,and sonicate,swirling the flask intermittently,until the tablet is dissolved.Dilute with water to volume,mix,and filter,discarding the first 50mLof the filtrate.Dilute a portion of the filtrate quantitatively and stepwise with 0.1Nsulfuric acid to obtain a solution having a concentration of about 1.25µg 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 1.25µg of USP Triprolidine Hydrochloride RSper mL,at the excitation wavelength of 300nm with a slit width of 2mm,and an emission wavelength of 460nm with a slit width of 2mm,with a suitable spectrophotometer,using 0.1Nsulfuric acid as the blank.Calculate the quantity,in mg,of C19H22N2·HCl·H2Oin the Tablet taken by the formula: in which 332.88and 314.86are the molecular weights of the monohydrate and anhydrous forms of triprolidine hydrochloride,respectively;Tis the labeled quantity,in mg,of triprolidine hydrochloride in the Tablet;Cis the concentration,in µg per mL,of USP Triprolidine Hydrochloride RSin the Standard solution;Dis 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,andIUandISare the fluorescence intensities of the solution from the Tablet and the Standard solution,respectively.

Mobile phaseand Standard preparation— Prepare as directed in theAssay underTriprolidine Hydrochlorides Syrup (Oral Solution,Official June 1,2005).

Assay preparation— Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 5.0mg of triprolidine hydrochloride,to a 100-mLvolumetric flask.Add about 10mLof 0.01Nhydrochloric acid,and sonicate for 10minutes.Cool to room temperature.Dilute with 0.01Nhydrochloric acid to volume,mix,and filter.

Chromatographic systemand Procedure— Proceed as directed in theAssay underTriprolidine Hydrochlorides Syrup (Oral Solution,Official June 1,2005),except to calculate the quantity,in mg,of triprolidine hydrochloride (C19H22N2·HCl·H2O)in the portion of Tablets taken by the formula: in which 332.88and 314.86are the molecular weights of triprolidine hydrochloride monohydrate and anhydrous triprolidine hydrochloride,respectively;Cis the concentration,in mg per mL,calculated on the anhydrous basis,of USP Triprolidine Hydrochloride RSin theStandard preparation;andrUandrSare the peak responses obtained from theAssay preparation and theStandard preparation,respectively.