Determination of melamine and malachite green by surface-enhanced Raman scattering spectroscopy using starch-coated silver nanoparticles as substrates

摘要

Silver nanoparticles (AgNPs) were synthesized by a classic method. The surface-enhanced Raman scattering (SERS) activity of the as-synthesized substrates was evaluated by measuring the SERS signals of several different target analytes. The influence of starch concentration on AgNPs was studied and 1.00% (w/v) of starch was selected. The starch-coated AgNPs displayed a higher stability than the classic AgNPs. The practical application of the starch-coated SERS substrate was evaluated by determination of melamine and malachite green. Under the optimal conditions, melamine and malachite green were determined in the ranges of 2.00a€“50.0 ??g La?’1 and 0.500a€“35.0 ??g La?’1 with correlation coefficients of 0.9992 and 0.9979, and the detection limits were 0.600 ??g La?’1 and 0.080 ??g La?’1, respectively. The recoveries of melamine in spiked milk samples and malachite green in water samples were 94a€“104% and 96a€“107%, respectively. These results foresee promising application of starch-coated AgNPs as sensitive SERS substrates in both food and environmental water.