A novel chemiluminescence sensor for the determination of indomethacin based on sulfur and nitrogen co‐doped carbon quantum dot–KMnO₄ reaction

We report on a simple and sensitive sulfur and nitrogen co‐doped carbon quantum dot (S,N‐CQD)‐based chemiluminescence (CL) sensor for the determination of indomethacin. S,N‐CQDs were prepared by a hydrothermal method and characterized by fluorescence spectra, Fourier transform infrared spectroscopy and transmission electron microscopy. To obtain the best CL system for determination of indomethacin, the reaction of S,N‐CQDs with some common oxidants was studied. Among the tested systems, the S,N‐CQD–KMnO 4 reaction showed the highest sensitivity for the detection of indomethacin. Under optimum conditions, the calibration plot was linear over a concentration range of 0.1–1.5 mg L −1 , with a limit of detection (3σ) of 65 μg L −1 . The method was applied to the determination of indomethacin in environmental and biological samples with satisfactory results.