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-KMnO4-HCl systems by comparing the fluorescence emission with CL spectra. The illuminant was the singlet-state bimolecular oxygen (O2O2)-O-1-O-1((1)Delta(1)(g)Delta(g)), which is from O-1(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 O-1(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. (c) 2007 Wiley-Liss, Inc.