Carbon nitride quantum dot-enhanced chemiluminescence of hydrogen peroxide and hydrosulfite and its application in ascorbic acid sensing

[摘要] Herein, weak chemiluminescence (CL) reaction of hydrogen peroxide and hydrosulfite was greatly enhanced by carbon nitride quantum dots (g-CNQDs). CL experiments and electron spin resonance (ESR) investigation indicated that g-CNQD increased the production of singlet oxygen (1O2), superoxide radical (˙O2−), and sulphite radical anion (˙SO3−) in the hydrogen peroxide–hydrosulfite CL system; this could be attributed to the enhanced-CL intensity and gave us new insights into the character of fluorescent carbon nitride quantum dots. Ascorbic acid exerted an inhibition effect on the CL of the hydrogen peroxide–hydrosulfite–g-CNQD CL system. This phenomenon was utilized as a determination method of ascorbic acid in the concentration ranging from 2.85 × 10−7 to 2.85 × 10−4 mol L−1, with a detection limit of 8.0 × 10−8 mol L−1. Ascorbic acid in tablets and injections has been successfully detected with recoveries in the range from 96.2% to 106%.

[学科分类] 分析化学