Sensitized chemiluminescence determination of fluorouracil in pharmaceutical and biological fluids based on potassium permanganate oxidation in the presence of formaldehyde.

A novel chemiluminescence (CL) reaction system was established for the anticancer drug fluorouracil (5-FU). We developed a formaldehyde-sensitized CL emission mechanism for 5-FU-KMnO(4)-HCl systems by comparing the fluorescence emission with CL spectra. The illuminant was the singlet-state bimolecular oxygen (1)O(2) (1)O(2)((1)Delta(g) (1)Delta(g)), which is from (1)O(2)((1)Delta(g)) produced in the reaction system, and emits CL spectra at 639 nm. The presence of formaldehyde can sensitize CL emission by accelerating the generation of (1)O(2)((1)Delta(g)). The optimum conditions for CL emission were investigated. The relationship between the relative CL intensity and the concentration of the analyte showed good linearity. The determination limit was 3 x 10(-8) g mL(-1). The relative standard deviation (SD) was 1.8%. The proposed method was applied to the determination of fluorouracil in pharmaceutical preparations and biological fluids, and satisfactory results were obtained. Copyright (c) 2007 Wiley-Liss, Inc.