Flow injection spectrofluorimetric method for the determination of cadmium

A novel fluorescent reagent, o-vanillin furoylhydrazone (OVFH), was synthesized, and its infrared spectrum, elemental analysis and dissociation constant are reported. The reaction between Cd2+ and OVFH produces an intensely fluorescent complex in ethanol-water medium of pH 10.00, and this finding has led to a simple, rapid, and sensitive flow injection (Fl) spectrofluorimetric method for on-line determination of Cd2+. Under the optimum experimental conditions, the fluorescent complex had excitation and emission maxima at 393 and 494 nm, respectively. The linear range is from 0.025 to 8.0 mg mL-1 of Cd2+, the detection limit is 7.6 mug L-1 and the maximum sampling rate is 80 h-1. The effect of interferences was studied. The method was successfully applied to the determination of cadmium in environmental samples.