Synthesis of novel decorated one-dimensional gold nanoparticle and its application in ultrasensitive detection of insecticide

Contamination of soil, groundwater and food with methyl parathion, which is one of the most hazardous insecticides, is causing wide concern. Motivated by the urgent demand for trace analysis of insecticide from environmental samples, searching for a novel highly sensitive or selective analytical approach has been a longstanding interest. The as-prepared one dimensional gold nanoparticles, with different aspect ratios, have been decorated with mono-6-thio-beta-cyclodextrin so as to efficiently capture and detect methyl parathion insecticide via a surface enhanced Raman scattering (SERS) technique for the first time. A detailed comparison among different aspect ratios of the one dimensional gold nanoparticles suggests that the one dimensional gold nanoparticles with aspect ratio 2 can be provided as an excellent SERS active substrate for detecting the insecticide in the present study. Due to the efficient formation of a host-guest complex between the hybridized cavity and methyl parathion, identification of the insecticide can be observed at picomolar level according to the fingerprint Raman peaks. Excellent sensitivity and selectivity for detection of the insecticide using the hybridized one dimensional gold nanoparticles without a Raman label indicate that it is a simple and ultrasensitive approach for detecting insecticides in contrast with some other traditional detection approaches.