A: Infrared Absorption á197Kñ.

B: Ultraviolet Absorption á197Uñ—

C: The retention time of the major peak in the chromatogram of the Assay preparationcorresponds to that in the chromatogram of the Standard preparation,as obtained in the Assay.

Test solution: 30mg per mL,in water.

Mobile phase andChromatographic system— Proceed as directed in the Assay.

Standard solution— Use the Standard preparationprepared as directed in the Assay.

Test solution— Use the Assay preparation.

Procedure— Proceed as directed in the Assay.Calculate the percentages of trifluridine related compound Aand 5-(trifluoromethyl)uracil in the portion of Trifluridine taken by the formula: in which Cis the concentration,in mg per mL,of USP Trifluridine Related Compound A RSand 5-(trifluoromethyl)uracil in the Standard solution;Wis the weight,in mg,of Trifluridine taken;and rUand rSare the peak responses for the related compounds obtained from the Test solutionand the Standard solution,respectively:not more than 1.0%of each related compound is found.

Mobile phase— Prepare a filtered and degassed 0.15%sodium citrate solution and adjust with 1Nhydrochloric acid to a pHof 6.8.Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).

Standard stock preparation— Dissolve accurately weighed quantities of USP Trifluridine RS,USP Trifluridine Related Compound A RS,and 5-(trifluoromethyl)uracil in water to obtain a solution having known concentrations of about 1mg per mL,0.01mg per mL,and 0.01mg per mL,respectively.[NOTE—This stock preparation may be stored at 0to 5for 3months.]

Standard preparation— Transfer 10.0mLof the Standard stock preparationto a 50-mLvolumetric flask,dilute with water to volume,and mix.

Assay preparation— Transfer about 50mg of Trifluridine,accurately weighed,to a 250-mLvolumetric flask,dissolve in and dilute with water to volume,and mix.

Chromatographic system (see Chromatography á621ñ)— The liquid chromatograph is equipped with a 254-nm detector and a 4.2-mm ×25-cm column that contains packing L1.The flow rate is about 2mLper minute.Chromatograph the Standard preparation,and record the peak responses as directed for Procedure:the resolution,R,between 5-(trifluoromethyl)uracil and trifluridine related compound Ais not less than 3.0and between trifluridine related compound Aand trifluridine is not less than 4.0;and the relative standard deviation for replicate injections is not more than 2.0%.

Procedure— Separately inject equal volumes (about 10µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the areas for the major peaks.Calculate the quantity,in mg,of C10H11F3N2O5in the portion of Trifluridine taken by the formula: in which Cis the concentration,in mg per mL,of USP Trifluridine RSin the Standard preparation;and rUand rSare the peak responses obtained from the Assay preparationand the Standard preparation,respectively.