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 (C
4H
3FN
2O
2) 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.