Abstract
A flow-injection electrochemiluminescent method for L-cysteine determination has been developed based on its enhancement of the electrochemiluminecence of luminol at a glassy carbon electrode. This method is simple and sensitive for cysteine determination. Under the selected experimental parameters, the linear range for cysteine concentration was 1.0 × 10-6 - 5.0 × 10-5 mol/l, and the detection limit was 0.67 μmol/l (S/N = 3). The relative standard deviation for 11 measurements of 1.0 × 10-5 mol/l cysteine was 4.5%. The proposed method has been applied to the detection of cysteine in pharmaceutical injections with satisfactory results.
