Thin layer chromatography combined with surface-enhanced raman spectroscopy for rapid sensing aflatoxins

A fast and facile method was developed for on-site detection of aflatoxins (AFs) in moldy agricultural products using thin layer chromatography combined with surface-enhanced Raman spectroscopy (TLC-SERS). Four different AFs were successfully separated by TLC and then a small portable Raman spectrometer, with gold colloids as the SERS-active substrate, was applied to identify the separated spots. TLC-SERS application to on-site detection of AFs was systematically investigated. Qualitative and quantitative AF detection was found to be easily accomplished and limits of detection were estimated to be 1.5 x 10(-6), 1.1 x 10(-5), 1.2 x 10(-6), and 6.0 x 10(-7) M for AFE(1), AFB(2), AFG(1), and AFG(2), respectively. The proposed method was also highly selective, enabling successful AF identifications in complex extracts from moldy peanuts. The study showed that TLC-SERS could be effectively used for separation and detection of these four AFs, demonstrating good prospects for on-site qualitative screening of agricultural products. (C) 2018 Elsevier B.V. All rights reserved.