Fluorouracil Topical Solution
» Fluorouracil Topical Solution contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of C4H3FN2O2.
Packaging and storage— Preserve in tight containers, and store at controlled room temperature.
USP Reference standards 11—
USP Fluorouracil RS Click to View Structure
Identification— It responds to the Identification test under Fluorouracil Cream.
Microbial enumeration tests 61 and Tests for specified microorganisms 62— It meets the requirements of the tests for absence of Staphylococcus aureus and Pseudomonas aeruginosa.
Assay—
Mobile phase, Standard preparation, and Chromatographic system— Proceed as directed in the Assay under Fluorouracil.
Assay preparation— Transfer an accurately weighed portion of Solution, equivalent to about 20 mg of fluorouracil, to a 100-mL volumetric flask, dilute with water to volume, and mix. Quantitatively dilute a volume of this solution with water to obtain a concentration of 10 µg per mL.
Procedure— Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the peak responses for the major peaks. Calculate the quantity, in mg, of fluorouracil (C4H3FN2O2) in the portion of Solution taken by the formula:
2C(rU / rS)
in which C is the concentration, in µg per mL, of USP Fluorouracil RS in the Standard preparation; and rU and rS are the fluorouracil responses obtained from the Assay preparation and the Standard preparation, respectively.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Feiwen Mao, M.S.
Senior Scientific Liaison
1-301-816-8320		 (SM32010) Monographs - Small Molecules 3
Reference Standards RS Technical Services
1-301-816-8129
rstech@usp.org
61 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339		 (GCM2010) General Chapters - Microbiology
62 Radhakrishna S Tirumalai, Ph.D.
Principal Scientific Liaison
1-301-816-8339		 (GCM2010) General Chapters - Microbiology
USP35–NF30 Page 3241