In this research, NiS nanoparticles (NPs) were produced using a hydrothermal technique and character- ized by several spectroscopic methods. Here, for the first time, it was shown that NiS NPs could be exploited as a nanocatalyst in a chemiluminescence (CL) reaction. Here, it was introduced that NiS NPs could intensify luminol-O2 CL reaction, remarkably. Besides, it was shown that vancomycin (VAN) sup- presses the CL intensity of NiS NPs-luminol-O2 reaction. By exploiting the results obtained, a new and straightforward CL method was developed for the measurement of VAN. The linear concentration range of the CL method was 4.00 10 6 – 1.00 10 3 mol L 1. The limit of detection (LOD) was equal to 1.40 10 6 mol L 1 and the relative standard deviation (RSD) of the CL method was 3.00% (n = 6) for the determination of 8.00 10 5 mol L 1 VAN. The established CL method was applied to quantify VAN in the injection and spiked human seru
