» Sulfinpyrazone Tablets contain not less than 93.0 percent and not more than 107.0 percent of the labeled amount of sulfinpyrazone (C23H20N2O3S).
Packaging and storage Preserve in well-closed containers.
USP Reference standards 11
Identification Finely powder a quantity of Tablets, equivalent to about 400 mg of sulfinpyrazone, boil with 20 mL of alcohol, and filter. Add water to the filtrate until the solution becomes turbid, allow to stand until crystals form (1 to 2 hours), remove the crystals by filtration, and dry at 105 for 1 hour: the sulfinpyrazone so obtained melts between 128 and 134, and responds to the Identification test under Sulfinpyrazone.
Medium: pH 6.8 phosphate buffer (see under Buffer Solutions in the section Reagents, Indicators, and Solutions); 900 mL.
Apparatus 1: 100 rpm.
Time: 45 minutes.
Procedure Determine the amount of C23H20N2O3S dissolved from UV absorbances at the wavelength of maximum absorbance at about 259 nm of filtered portions of the solution under test, suitably diluted with Dissolution Medium, in comparison with a Standard solution having a known concentration of USP Sulfinpyrazone RS in the same Medium.
Tolerances Not less than 75% (Q) of the labeled amount of C23H20N2O3S is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Acetonitrile and tetrahydrofuran mixture , Mobile phase, Internal standard solution, Standard preparation, Chromatographic system, and ProcedureProceed as directed in the Assay for Sulfinpyrazone Capsules.
Assay preparation Weigh and finely powder not less than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 100 mg of sulfinpyrazone, to a 200-mL volumetric flask, add 100 mL of acetonitrile, mix, add 10.0 mL of Internal standard solution, dilute with acetonitrile to volume, and mix. Filter, discarding the first 5 mL of the filtrate.
Auxiliary Information Please check for your question in the FAQs before contacting USP.
USP35NF30 Page 4725