Real-time monitoring of fenitrothion in water samples using a silicon nanophotonic biosensor

Due to the large quantities of pesticides extensively used and their impact on the environment and human health, a prompt and reliable sensing technique could constitute an excellent tool for in-situ monitoring. With this aim, we have applied a highly sensitive photonic biosensor based on a bimodal waveguide interferometer (BiMW) for the rapid, label-free, and specific quantification of fenitrothion (FN) directly in tap water samples. After an optimization protocol, the biosensor achieved a limit of detection (LOD) of 0.29 ng mL(-1) (1.05 nM) and a half-maximal inhibitory concentration (IC50) of 1.71 ng mL(-1) (6.09 nM) using a competitive immunoassay and employing diluted tap water. Moreover, the biosensor was successfully employed to determine FN concentration in blind tap water samples obtaining excellent recovery percentages with a time-to-result of only 20 min without any sample pretreatment. The features of the biosensor suggest its potential application for real time, fast and sensitive screening of FN in water samples as an analytical tool for the monitoring of the water quality. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Due to the impact of pesticides on the environment and human health, a sensitive photonic biosensor was developed for the rapid and specific detection of fenitrothion in tap water. After optimization, the biosensor achieved a low limit of detection and was successfully used for quantification in blind tap water samples within 20 minutes without pretreatment.