Simple and selective detection of pendimethalin herbicide in water and food samples based on the aggregation of ractopamine-dithiocarbamate functionalized gold nanoparticles

In this work, a simple, selective and sensitive colorimetric method was developed for the detection of pendimethalin herbicide using ractopamine-dithiocarbamate capped gold nanoparticles (RAC-DTC-Au NPs) as a probe. The pendimethalin was effectively induced the aggregation of RAC-DTC-Au NPs via various interactions (donor-acceptor, pi-pi, van der Waals and hydrogen-bonding), resulting a color change from red to blue. As a result, the linear graph was plotted between the absorption ratio at A(650)/A(522) and the pendimethalin concentration in the range of 5.0-500 mu M. The detection limit was found to be 0.22 mu M, which is very close to the maximum residue limit (MRL) of pendimethalin that was established by European Commission. The proposed method was successfully applied to detect pendimethalin in environmental water and food samples with good recoveries. (C) 2017 Elsevier B.V. All rights reserved.