Chemiluminescence determination of naproxen based on europium(III)-sensitized KIO4-H2O2 reaction.

A simple and sensitive chemiluminescence (CL) method combined with flow injection technique was developed for the determination of naproxen. It was based upon the weak CL signal arising from the reaction of KIO(4) with H(2)O(2) being significantly increased by naproxen in the presence of europium(III) ion. The experimental conditions that affected the CL signal were carefully optimized and the CL reaction mechanism was briefly discussed. Under the optimum conditions, the increment of CL intensity was proportional to the concentration of naproxen ranging from 5.0 x 10(-8) to 5.0 x 10(-6) g/mL. The detection limit was 1 x 10(-8) g/mL naproxen and the relative standard deviation for 5.0 x 10(-7) g/mL naproxen solution was 2.1% (n = 11). The proposed method was applied to the determination of naproxen in tablets and in spiked human urine samples with satisfactory results.