Phenmetrazine Hydrochloride Tablets
»Phenmetrazine Hydrochloride Tablets contain not less than 93.0percent and not more than 107.0percent of the labeled amount of C11H15NO·HCl.
Packaging and storage— Preserve in tight containers.
Identification— Dissolve 5Tablets in 40mLof water in a 250-mLseparator.Add 3mLof sodium hydroxide solution (1in 2),and extract with two 50-mLportions of chloroform.Extract the combined chloroform extracts in a 250-mLseparator with two 15-mLportions of 0.5Nhydrochloric acid,and evaporate the combined aqueous extracts on a steam bath to dryness.Dissolve the residue in 5mLof acetone,and add 50mLof 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 3between 172and 182(see Melting Range or Temperature á741ñ).
Dissolution á711ñ—
Medium: water;900mL.
Apparatus 2: 50rpm.
Time: 45minutes.
Procedure— Determine the amount of C11H15NO·HCl dissolved from UVabsorbances at the wavelength of maximum absorbance at about 256nm 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 RSin the same Medium.
Tolerances— Not less than 75%(Q)of the labeled amount of C11H15NO·HCl is dissolved in 45minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Assay— Weigh and finely powder not fewer than 20Tablets.Transfer an accurately weighed portion of the powder,equivalent to about 250mg of phenmetrazine hydrochloride,to a 250-mLvolumetric flask,add about 125mLof 0.5Nhydrochloric acid,shake by mechanical means for 1hour,dilute with 0.5Nhydrochloric acid to volume,and mix.Transfer 50.0mLof the solution to a 250-mLseparator,add 5mLof sodium hydroxide solution (1in 2),and extract with four 50-mLportions of chloroform,collecting the chloroform extracts in a second 250-mLseparator.Extract the combined chloroform extracts with six 15-mLportions of 0.5Nhydrochloric acid,collecting the aqueous extracts in a 100-mLvolumetric flask,and dilute with 0.5Nhydrochloric acid to volume to obtain the Assay preparation.Concomitantly determine the absorbances of the Assay preparationand of a Standard solution of USP Phenmetrazine Hydrochloride RSin the same medium,having a known concentration of about 500µg per mL,in 1-cm cells,at the wavelength of maximum absorbance at about 256nm,with a suitable spectrophotometer,using 0.5Nhydrochloric 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 Cis the concentration,in µg per mL,of USP Phenmetrazine Hydrochloride RSin the Standard solution,and AUand ASare the absorbances from the Assay preparationand the Standard solution,respectively.
Auxiliary Information— Staff Liaison:Daniel K.Bempong,Ph.D.,Scientist
Expert Committee:(PA2)Pharmaceutical Analysis 2
USP28–NF23Page 1529
Phone Number:1-301-816-8143