Simultaneous determination of cysteine, ascorbic acid and uric acid by capillary electrophoresis with electrochemiluminescence

► Cysteine enhanced ECL intensity of tris(2,2′-bipyridyl) ruthenium(II)/tripropyl amine. ► Ascorbic acid (AA) and uric acid (UA) inhibited ECL intensities of this system. ► Wide linear range with low detection limit for the detection of cysteine. ► Efficient detection of cysteine with AA and UA. ► A useful method to detect cysteine, AA, and UA in biological samples.