Carbon dots-modified paper-based chemiluminescence device for rapid determination of mercury (II) in cosmetics

Here, a simple and portable paper-based analytical device (PAD) based on the inherent capability of carbon quantum dots (CQDs) to serve as a great emitter for the bis (2,4,6-trichlorophenyl)oxalate (TCPO)- hydrogen peroxide (H2O2) chemiluminescence (CL) reaction is introduced for the detection of harmful mercury ions (Hg2+). The energy is transferred from the unstable reaction intermediate (1,2-dioxetanedione) to CQDs, as acceptors, and an intensive orange-red CL emission is generated at similar to 600 nm, which is equal to the fluorescence emission wavelength of CQDs. The analytical applicability of this system was examined for the determination of Hg2+. It was observed that Hg2+ could significantly quench the produced emission, which can be attributed to the formation of a stable and nonluminescent Hg-2(+)-CQDs complex. Accordingly, a simple and rapid PAD was established for monitoring Hg2+, with a limit of detection of 0.04 mu g ml(-1). No interfering effect on the signal was found from other examined cations, indicating the acceptable specificity of the method. The designed assay was appropriately utilized to detect Hg2+ ions in cosmetic samples with high efficiency. It was characterized by its low cost, ease of use, and was facile but accurate and high selective for the detection of Hg2+ ions. In addition, the portability of this probe makes it suitable for on-site screening purposes.