Abstract: A new flow-injection chemiluminescence method for the determination of 5-sulfosalicylic acid was proposed. Various factors affected the chemiluminescence signal were investigated and the possible mechanism was also studied. Under the optimum conditions, the linear range for the determination of 5-sulfosalicylic acid was 5.0×10-8~2.0×10-5 mol/L with a detection limit(S/N=3) of 1.0×10-8 mol/L. The relative standard deviation was 2.7% for 5.0×10-6 mol/L 5-sulfosalicylic acid solution in nine repeated measurements. The method was successfully applied to the determination of 5-sulfosalicylic acid in the waste water of doxycycline.

Key words: flow-injection, chemiluminescence, Dichlorofluorescein, sulfosalicylic acid