A facile optical sensing strategy for glyphosate detection based on the structure-switching signaling aptamers

Abstract

Herein, a facile optical sensing strategy for glyphosate (GLYP) detection is established with high specificity using structure-switching signaling aptamers. The specific structure-switching aptamers (F-SSSAs) with fluorescence signal reporting functionality were initially designed. It involves two domains: the FITC-labeled signal transduction domain that controls the fluorescence signal reporting, and the functional domain (specific structure-switching aptamers) that controls the target recognition as well as high affinity for graphene oxide (GO). In this strategy, GO works as a robust quencher for F-SSSAs in the absence of GLYP. However, the structure of F-SSSAs switched in the presence of GLYP, which prominently affected the interaction between F-SSSAs and GO. And the fluorescence of the structure-switching signaling aptamer-based sensing system subsequently restored. The present optical sensing strategy exhibited two dynamic linear relationships for GLYP detection within the range from 0.2 to 80 ng·mL^− 1 and from 100 to 800 ng·mL^− 1 respectively, with a low detection limit (LOD) of 0.07 ng·mL^− 1. Significantly, the fluorescence-based sensing strategy was successfully utilized to detect GLYP in water, soil and rice with satisfactory outcomes, which suggested that it held potential applications prospect in monitoring GLYP.