Chemiluminescence of carbon dots induced by diperiodato-nicklate (IV) in alkaline solution and its application to a quenchometric flow-injection assays of paracetamol, L-cysteine and glutathione

Aqueous solutions of carbon dots (C-dots) were prepared by microwave-assisted thermal carbonization of poly(ethylene glycol). They were investigated by transmission electron microscopy, absorption and fluorescence spectra. It is shown that diperiodato-nicklate(IV), a strong oxidant, induces the chemiluminescence (CL) of C-dots in strongly alkaline solution without use of an additional reagent. A mechanism for this reaction is suggested. It is also found that the CL of the system is quenched by paracetamol, L-cysteine and glutathione. Under the optimized conditions, the calibration plot is linear with a correlation coefficient (r) of > 0.995. The limits of detection are 90, 8, and 60 A mu g L-(1) for paracetamol, L-cysteine, and glutathione, respectively. Spiked urine and serum samples were analyzed and gave recoveries in the range from 84.38 to 116.0 %, with an RSD of 1.2-2.7 %.