A: Transfer a quantity of powdered Tablets, equivalent to about 50 mg of meperidine hydrochloride, to a separator, add 10 mL of water, and shake. Add 5 mL of saturated sodium chloride solution and 1 mL of sodium hydroxide solution (1 in 25). Extract with three 20-mL portions of chloroform, filtering the extracts through cotton overlaid with anhydrous sodium sulfate. Evaporate the chloroform on a steam bath, and dissolve the residue in 4 mL of carbon disulfide. In a second separator, prepare a similar solution, using 50 mg of USP Meperidine Hydrochloride RS. Proceed as directed under Identification—Organic Nitrogenous Bases 181, beginning with “Determine the absorption spectra.”

B: The retention time of the major peak in the chromatogram of the Assay preparation corresponds to that obtained in the Standard preparation obtained in the Assay.

Medium: water; 500 mL.

Apparatus 1: 100 rpm.

Time: 45 minutes.

Procedure— Determine the amount of C15H21NO2·HCl dissolved employing the procedure set forth in the Assay, using filtered portions of the solution under test, suitably diluted with Dissolution Medium, if necessary, in comparison with a Standard solution having a known concentration of USP Meperidine Hydrochloride RS in the same Medium.

Tolerances— Not less than 75% (Q) of the labeled amount of C15H21NO2·HCl is dissolved in 45 minutes.

Buffer solution , Mobile phase, Chromatographic system, and Standard preparation—Proceed as directed in the Assay under Meperidine Hydrochloride.

Assay preparation— Weigh and grind not less than 20 Tablets to a fine powder. Transfer an accurately weighed portion of the powder, equivalent to about 60 mg of meperidine hydrochloride, to a 100-mL volumetric flask, add about 70 mL of Mobile phase, and sonicate for 10 minutes with occasional shaking. Shake by mechanical means for about 30 minutes, dilute with Mobile phase to volume, mix, and filter. Transfer 5.0 mL of the filtered solution to a 25-mL volumetric flask, dilute with Mobile phase to volume, and mix.

Procedure— Proceed as directed for Procedure in the Assay under Meperidine Hydrochloride. Calculate the quantity, in mg, of C15H21NO2·HCl in the portion of Tablets taken by the formula: in which C is the concentration, in mg per mL, of USP Meperidine Hydrochloride RS in the Standard preparation, and rU and rS are the meperidine peak responses obtained from the Assay preparation and the Standard preparation, respectively.