Phenmetrazine Hydrochloride Tablets
» Phenmetrazine Hydrochloride Tablets contain not less than 93.0 percent and not more than 107.0 percent of the labeled amount of C11H15NO·HCl.
Packaging and storage— Preserve in tight containers.
USP Reference standards 11
USP Phenmetrazine Hydrochloride RS Click to View Structure
Identification— Dissolve 5 Tablets in 40 mL of water in a 250-mL separator. Add 3 mL of sodium hydroxide solution (1 in 2), and extract with two 50-mL portions of chloroform. Extract the combined chloroform extracts in a 250-mL separator with two 15-mL portions of 0.5 N hydrochloric acid, and evaporate the combined aqueous extracts on a steam bath to dryness. Dissolve the residue in 5 mL of acetone, and add 50 mL of anhydrous ether to the solution. On standing, phenmetrazine hydrochloride will crystallize out. Filter the precipitate, wash with anhydrous ether, and dry at 105: the crystals so obtained melt within a range of 3 between 172 and 182 (see Melting Range or Temperature 741).
Dissolution 711
Medium: water; 900 mL.
Apparatus 2: 50 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C11H15NO·HCl dissolved from UV absorbances at the wavelength of maximum absorbance at about 256 nm on 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 Phenmetrazine Hydrochloride RS in the same Medium.
Tolerances— Not less than 75% (Q) of the labeled amount of C11H15NO·HCl is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Assay— Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 250 mg of phenmetrazine hydrochloride, to a 250-mL volumetric flask, add about 125 mL of 0.5 N hydrochloric acid, shake by mechanical means for 1 hour, dilute with 0.5 N hydrochloric acid to volume, and mix. Transfer 50.0 mL of the solution to a 250-mL separator, add 5 mL of sodium hydroxide solution (1 in 2), and extract with four 50-mL portions of chloroform, collecting the chloroform extracts in a second 250-mL separator. Extract the combined chloroform extracts with six 15-mL portions of 0.5 N hydrochloric acid, collecting the aqueous extracts in a 100-mL volumetric flask, and dilute with 0.5 N hydrochloric acid to volume to obtain the Assay preparation. Concomitantly determine the absorbances of the Assay preparation and of a Standard solution of USP Phenmetrazine Hydrochloride RS in the same medium, having a known concentration of about 500 µg per mL, in 1-cm cells, at the wavelength of maximum absorbance at about 256 nm, with a suitable spectrophotometer, using 0.5 N hydrochloric acid as the blank. Calculate the quantity, in mg, of C11H15NO·HCl in the portion of Tablets taken by the formula:
0.5C(AU / AS)
in which C is the concentration, in µg per mL, of USP Phenmetrazine Hydrochloride RS in the Standard solution, and AU and AS are the absorbances from the Assay preparation and the Standard solution, respectively.
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