A rapid high-performance liquid chromatographic method for quantitation of 5-fluorouracil in plasma after continuous intravenous infusion.

A fast, simple, precise, high-performance liquid chromatographic method for the assay of 5-fluorouracil in plasma from humans receiving continuous intravenous infusion is described. After a single extraction, underivatised 5-fluorouracil is assayed by high-performance liquid chromatography using a variable-wavelength ultraviolet detector. After extraction of 1 ml plasma, 0.3 mumol/l can be assayed. The assay is reproducible and linear up to at least 40 mumol/l. A single determination takes 3 hours and a batch of 40 specimens can be extracted and assayed in 4 working hours if automated equipment is used, enabling injections and calculations to be done overnight.