Related compounds
Mobile phase and Chromatographic system
Proceed as directed in the
Assay.
Standard solution
Use the
Standard preparation prepared 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 A and 5-(trifluoromethyl)uracil in the portion of Trifluridine taken by the formula:
25,000(C / W)(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Trifluridine Related Compound A RS and 5-(trifluoromethyl)uracil in the
Standard solution; W is the weight, in mg, of Trifluridine taken; and
rU and
rS are the peak responses for the related compounds obtained from the
Test solution and the
Standard solution, respectively: not more than 1.0% of each related compound is found.
Assay
Mobile phase
Prepare a filtered and degassed 0.15% sodium citrate solution and adjust with 1 N hydrochloric acid to a pH of 6.8. Make adjustments if necessary (see
System Suitability under
Chromatography 621).
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 1 mg per mL, 0.01 mg per mL, and 0.01 mg per mL, respectively.
[NOTEThis stock preparation may be stored at 0
to 5
for 3 months.
]
Standard preparation
Transfer 10.0 mL of the Standard stock preparation to a 50-mL volumetric flask, dilute with water to volume, and mix.
Assay preparation
Transfer about 50 mg of Trifluridine, accurately weighed, to a 250-mL volumetric flask, dissolve in and dilute with water to volume, and mix.
Chromatographic system (see Chromatography 621)
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 2 mL per 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 A is not less than 3.0 and between trifluridine related compound A and 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 10 µL) of the
Standard preparation and the
Assay preparation into the chromatograph, record the chromatograms, and measure the areas for the major peaks. Calculate the quantity, in mg, of C
10H
11F
3N
2O
5 in the portion of Trifluridine taken by the formula:
250C(rU / rS),
in which
C is the concentration, in mg per mL, of
USP Trifluridine RS in the
Standard preparation; and
rU and
rS are the peak responses obtained from the
Assay preparation and the
Standard preparation, respectively.