»Sulfinpyrazone contains not less than 98.5 percent and not more than 101.5 percent of C23H20N2O3S, calculated on the dried basis.
Packaging and storage Preserve in well-closed containers.
Solubility in acetone A 250-mg portion dissolves in 5.0 mL of acetone to yield a clear, practically colorless solution.
Solubility in 0.50 N sodium hydroxide A 0.50-g portion dissolves in 10.0 mL of 0.50 N sodium hydroxide to yield a clear, practically colorless solution.
Identification, Infrared Absorption 197K.
Melting range 741: between 130.5 and 134.5.
Loss on drying 731 Dry it at 105 for 2 hours: it loses not more than 0.5% of its weight.
Residue on ignition 281: not more than 0.1%.
Heavy metals, Method II 231: 0.001%.
Mobile phase Proceed as directed in the Assay under Sulfinpyrazone Capsules.
Acetate buffer Transfer 240 mL of 0.1 N acetic acid to a 1-liter flask. Add 200 mL of 0.1 N potassium hydroxide, mix, and dilute with water to volume. Adjust to a pH of 5.0.
Diluting solution Prepare a mixture of acetonitrile and Acetate buffer (4:1).
Standard preparation Dissolve an accurately weighed quantity of USP Sulfinpyrazone RS in Diluting solution, and dilute quantitatively, and stepwise if necessary, with Diluting solution to obtain a solution having a known concentration of about 10 µg per mL.
Test preparation Prepare a solution of Sulfinpyrazone in Diluting solution having a known concentration of about 2 mg per mL.
Chromatographic system (see Chromatography 621)Proceed as directed in the Assay under Sulfinpyrazone Capsules. Chromatograph the Standard preparation, and record the peak responses as directed for Procedure: the retention time for sulfinpyrazone is between 4.0 and 4.6 minutes, the tailing factor is not more than 2.0, and the relative standard deviation for replicate injections is not more than 2.0%.
Procedure Separately inject equal volumes (about 10 µL) of the Standard preparation and the Test preparation into the chromatograph, record the chromatograms, and measure the responses for all of the peaks: the sum of the peak responses, other than that of the sulfinpyrazone peak, from the Test preparation is not more than four times the sulfinpyrazone peak response from the Standard preparation (2.0%), and no single peak response is greater than twice the sulfinpyrazone peak response from the Standard preparation (1.0%).
Assay Dissolve about 600 mg of Sulfinpyrazone, accurately weighed, in 50 mL of neutralized alcohol, with slight heating. Add phenolphthalein TS, and titrate with 0.1 N sodium hydroxide VS. Each mL of 0.1 N sodium hydroxide is equivalent to 40.45 mg of C23H20N2O3S.
Auxiliary Information Please check for your question in the FAQs before contacting USP.Chromatographic Column
USP32NF27 Page 3634Pharmacopeial Forum: Volume No. 34(6) Page 1483
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.