A novel permanganate-morin-CdS quantum dots flow injection chemiluminescence system for sensitive determination of vancomycin

A novel and sensitive flow injection chemiluminescence (CL) method was introduced for the determination of vancomycin based on implementation of l-cysteine capped cadmium sulphide quantum dots (CdS QDs) as a sensitizer in a KMnO₄-morin CL system. Investigation of the optical and structural characteristics of the CdS QDs synthesized via a hydrothermal method was accomplished by applying X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence (PL), Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-Vis) spectroscopy. Furthermore, the possible mechanism of the proposed CL system was discussed by exploiting the results of the kinetic curves of the CL systems and the spectra of CL, PL, and UV-Vis analysis. The CL intensity of the KMnO₄-morin-CdS QDs system was significantly enhanced in the presence of vancomycin. Under the optimized conditions, the increased CL intensity was proportional to vancomycin concentration in the range of 0.004-19 mg L^-1, with a detection limit (3σ) of 1.4 μg L^-1. Moreover, the proposed CL method was successfully applied for the determination of vancomycin in environmental water samples and commercial pharmaceutical formulations.