Fluorouracil Cream
»Fluorouracil Cream contains not less than 90.0percent and not more than 110.0percent of the labeled amount of fluorouracil (C4H3FN2O2).It may contain Sodium Hydroxide to adjust the pH.
Packaging and storage— Preserve in tight containers,and store at controlled room temperature.
Identification— Prepare a test solution by placing a quantity of Cream,equivalent to about 5mg of fluorouracil,in a glass-stoppered conical flask,add 50mLof alcohol,and shake until dissolved.Dissolve 5mg of USP Fluorouracil RSin 50mLof alcohol to obtain a Standard solution.In 20-µLincrements,apply 100µLeach of the Standard solution and the test solution to a line about 3cm from the bottom edge of a thin-layer chromatographic plate coated with a 0.25-mm layer of chromatographic silica gel mixture,which previously has been dried and activated at 105for 5minutes.Develop the chromatogram in a solvent system consisting of a mixture of ethyl acetate,methanol,and ammonium hydroxide (75:25:1),allowing the solvent front to move about 15cm beyond the initial spotting line.Remove the plate,air-dry for 15minutes,and examine under short-wavelength UVlight:the RFvalue of the principal spot obtained from the test solution corresponds to that obtained from the Standard solution.
Microbial limits á61ñ— It meets the requirements of the tests for absence of Staphylococcus aureusand Pseudomonas aeruginosa.
Minimum fill á755ñ: meets the requirements.
Assay—
Mobile phase ,Standard preparation,and Chromatographic system—Proceed as directed in the Assayunder Fluorouracil.
Assay preparation— Transfer an accurately weighed portion of Cream,equivalent to about 10mg of fluorouracil,to a 100-mLvolumetric flask,add 20mLof methanol,and mix on a vortex mixer to dissolve.Dilute with water to volume,and mix.Transfer 1.0mLof this solution to a 10-mLvolumetric flask,dilute with water to volume,mix,and filter.
Procedure— Separately inject equal volumes (about 10µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of fluorouracil (C4H3FN2O2)in the portion of Cream taken by the formula:
C(rU/rS),
in which Cis the concentration,in µg per mL,of USP Fluorouracil RSin the Standard preparation;and rUand rSare the fluorouracil peak responses obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(PA6)Pharmaceutical Analysis 6
USP28–NF23Page 852
Phone Number:1-301-816-8389