Aminobenzoate Potassium Capsules
»Aminobenzoate Potassium Capsules contain not less than 90.0percent and not more than 110.0percent of the labeled amount of aminobenzoate potassium (C7H6KNO2).
Packaging and storage— Preserve in well-closed containers.
Identification— Dissolve about 1g of the Capsule contents in 25mLof water,add 5mLof 3Nhydrochloric acid,and wash the precipitate with two 5-mLportions of cold water.Recrystallize from alcohol the precipitate so obtained,and dry at 110for 1hour:the p-aminobenzoic acid so obtained melts between 186and 189.
Dissolution á711ñ—
Medium: water;900mL.
Apparatus 1: 100rpm.
Time: 45minutes.
Procedure— Determine the amount of C7H6KNO2dissolved by employing UVabsorption at the wavelength of maximum absorbance at about 270nm on filtered portions of the solution under test,suitably diluted with Medium,in comparison with a Standard solution having a known concentration of USP Aminobenzoate Potassium RSin the same Medium.
Tolerances— Not less than 75%(Q)of the labeled amount of C7H6KNO2is dissolved in 45minutes.
Uniformity of dosage units á905ñ: meet the requirements.
Assay—
Standard preparation— Prepare a solution of USP Aminobenzoate Potassium RShaving a known concentration of about 5µg per mL.
Assay preparation— Remove as completely as possible,and combine,the contents of not fewer than 20Capsules.Transfer an accurately weighed portion of the combined contents,equivalent to about 100mg of aminobenzoate potassium,to a 200-mLvolumetric flask,add 150mLof water,shake by mechanical means for 30minutes,dilute with water to volume,mix,and filter.Pipet 2mLof the filtrate into a 200-mLvolumetric flask,dilute with water to volume,and mix.
Procedure— Concomitantly determine the absorbances of the Standard preparationand the Assay preparationat the wavelength of maximum absorbance at about 270nm,with a suitable spectrophotometer,using water as the blank.Calculate the quantity,in mg,of aminobenzoate potassium (C7H6KNO2)in the portion of Capsule contents taken by the formula:
20C(AU/AS),
in which Cis the concentration,in µg per mL,of USP Aminobenzoate Potassium RSin the Standard preparation;and AUand ASare the absorbances of the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Clydewyn M.Anthony,Ph.D.,Scientist
Expert Committee:(PA2)Pharmaceutical Analysis 2
USP28–NF23Page 120
Phone Number:1-301-816-8139