Glutathione-s-transferase based electrochemical biosensor for the detection of captan

The proposed electrochemical biosensor based on the inhibition of glutathione-s-transferase (GST) onto SAM modified gold due to captan was developed and determined by CV technique. The bioelectrode exhibited improved fast response time (12 s) with the detection lit-nits 0.25-16 ppm, percentage inhibition >72% and high sensitivity 4.5 uA/ppm at standard optimal conditions. The recovery experiment results were found between 77% and 144% from spiked water sources. The bioelectrode was regenerated by DTT and reusable. The bioelectrodes were characterized by UV-visible, CV, AFM and STM. Thus, the proposed electrochemical biosensor is not only detected captan but also its metabolite and promising for real-time analysis of small molecules of environmental interest. (c) 2008 Elsevier B.V. All rights reserved.