Ionic liquid functionalized gold nanoparticles: Synthesis, rapid colorimetric detection of imidacloprid

A novel strategy for the fabrication of a highly selective and sensitive imidacloprid probe based on imidazole ionic liquid (IL) modified gold nanoparticles (I-IL-Au NPs) was developed. The resulting gold nanoparticles were characterized by UV–vis spectroscopy, IR spectroscopy, transmission electron microscopy (TEM). The newly synthesized gold nanoparticles had a cooperative effect on recognition of imidacloprid in aqueous solution resulting in appreciable changes in color and absorption properties over other 13 pesticides tested. The advantage of our system over classical assays is that it can realize the prompt on-site and real-time detection of imidacloprid with high sensitivity (5 × 10−7 M) in aqueous solution. Moreover, the detection system can be applied to the determination of imidacloprid in real different water samples such as the Yangtze River sample and East Lake water samples with the limit of colorimetric detection as low as 1.0 × 10−5 M and 1.0 × 10−6 M. In addition, our detection system can realize relatively effective removal of imidacloprid.