A: Triturate a portion of finely powdered Tablets,equivalent to about 10mg of procyclidine hydrochloride,with 20mLof chloroform,filter,evaporate the filtrate on a steam bath to dryness,and dry the residue at 105for 1hour:the IRabsorption spectrum of a potassium bromide dispersion of the procyclidine hydrochloride so obtained exhibits maxima only at the same wavelengths as that of a similar preparation of USP Procyclidine Hydrochloride RS.

B: Aportion of finely powdered Tablets,equivalent to about 50mg of procyclidine hydrochloride,responds to Identificationtest Bunder Procyclidine Hydrochloride.

Medium: water;900mL.

Apparatus 2: 50rpm.

Time: 45minutes.

Procedure— Determine the amount of C19H29NO·HCl dissolved,employing the procedure set forth in the Assay,making any necessary modifications.

Tolerances— Not less than 75%(Q)of the labeled amount of C19H29NO·HCl is dissolved in 45minutes.

Bromocresol purple solution— Dissolve 250mg of bromocresol purple in dilute glacial acetic acid (1in 50)to make 1000mL.

Standard preparation— Transfer about 25mg of USP Procyclidine Hydrochloride RS,accurately weighed,to a 100-mLvolumetric flask,add water to volume,and mix.Transfer 10.0mLof this solution to a second 100-mLvolumetric flask,dilute with Bromocresol purple solutionto volume,and mix.The concentration of the Standard preparationis about 25µg per mL.

Assay preparation— Weigh and finely powder not less than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 2.5mg of procyclidine hydrochloride,to a 100-mLvolumetric flask,add 10.0mLof water,and mix.Dilute with Bromocresol purple solutionto volume,mix,and allow the undissolved particles to settle.Use the supernatant as directed in the Procedure.

Procedure— Transfer 5.0mLeach of the Standard preparationand the Assay preparationto individual 60-mLseparators.Transfer 0.5mLof water and 4.5mLof Bromocresol purple solutionto a third separator to provide the blank.Extract each solution with 20.0mLof chloroform,and filter each extract,discarding the first 5mLof the filtrate.Concomitantly determine the absorbance of each subsequent filtrate in a 1-cm cell at the wavelength of maximum absorbance at about 405nm,with a suitable spectrophotometer,against the blank.Calculate the quantity,in mg,of C19H29NO·HCl in the portion of Tablets taken by the formula: in which Cis the concentration,in µg per mL,of USP Procyclidine Hydrochloride RSin the Standard preparation,and AUand ASare the absorbances of the solutions from the Assay preparationand the Standard preparation,respectively.