Lanthanum ions assisted non-enzymatic ratiometric fluorescence probe for monitoring fenthion residues in agro-product samples

Abstract

In this work, a La3+ assisted glutathione-capped gold nanoclusters and carbon dots (GSH-Au NCs/CDs) nanoplatform for sensitive detection of fenthion (FEN) is fabricated. The fluorescence response of GSH-Au NCs significantly increases due to aggregation-induced emission enhancement (AIEE) effect induced by La3+, which is further enhanced with adding FEN due to the coordination between La3+ and FEN. Taking the fluorescence intensity of CDs as the signal background, the ratiometric fluorescence of GSH-Au NCs and CDs has a good linear relationship with the FEN concentration from 0.01 to 1.10 μg mL−1, and detecting FEN exhibits a good sensitivity at a low detection limit of 6.74 ng g−1. The La3+ assisted GSH-Au NCs/CDs nanoplatform demonstrates desirable selectivity and applicability for monitoring trace level of FEN in fruit and vegetable samples. The non-enzymatic strategy by taking advantage of successive AIEE of GSH-Au NCs has a great potential for facile screening organophosphate pesticides in agro-products.