Rapid on-site TLC-SERS Detection of Four Sleep Problems Drugs Used as Adulterants in Health-Care Food

A novel facile method for on-site detection of sleep problems chemicals (e.g. triazolam, estazolam, clonazepam and oxazepam) adulterated in health-care food for promoting sleep using thin layer chromatography (TLC) combined with surface enhanced Raman spectroscopy (SERS) was reported in the present paper. Firstly, chemical drugs added in simulation of positive drugs were separated with substrate in health-care food by TLC initially, mobile phase was cyclohexane-ethyl acetate-ethanol (5:3. 5:2); detected and located by UV under 254 nm. Then trace substances were qualitative detected by SERS, excitation wavelength was 780 nm, surface enhancer was aqueous phase silver sol. The effect of matrix on the addition of health-care food was investigated by TLC-SERS in the positive experiment, and the detection limits of the 4 kinds of chemical components were also investigated. TLC-SERS detection method for 4 kinds of chemical components, which were illegally added in sleep health care products, was established. The characteristic peaks of Raman spectra of the chemical drugs added into health-care food obtained by TLC-SERS method were nearly consistent with the reference substance. TLC-SERS of matrix of health-care food to add ingredients was almost no interference. The LOD of 4 kinds of chemical components was from 1 to 4 mu g. In addition, commercially available five kinds of Chinese medicine and health-care food for improving sleep were tested, randomly; there was no illegal substance added in the case. In this study, TLC-SERS method is applied in rapid testing of health-care food adulteration for the first time, with obtaining some ideal results, such as SERS spectra of 4 kinds of sedative hypnotics chemical drugs, as well as TLC-SERS detection methods for 4 frequently adulterated sedative hypnotics chemical drugs. TLC-SERS method is specific, sensitive, rapid, and without significant detection time constraints, would have good prospects in on-site detection of chemicals for doping in health-care food.