A simple colorimetric kit for determination of ketamine hydrochloride in water samples

A sensitive, selective, on-site and rapid colorimetric kit has been developed for the determination of ketamine hydrochloride. The method was based on immobilization of a cobalt complex on to a nano-SiO2 (NS) support. The product of the reaction between the solution containing ketamine hydrochloride and the basic cobalt tetrathiocyanate@NS support generates a purple precipitate in a spot plate or a test tube. The purple color intensity depends on the concentration of ketamine hydrochloride, complex and support amounts. This developed test kit could be employed to detect ketamine hydrochloride at a very low concentration (0.01 mg mL(-1)) within 5 seconds. This detection assay can also detect different concentrations of ketamine hydrochloride in water via RGB image analysis (red, green, and blue color value changes). The basic cobalt tetrathiocyanate@NS support was characterized by FT-IR spectroscopy, CHNS and scanning electron microscopy (SEM). This test kit is highly sensitive, rapid, and cost effective.