Fluorescent carbon dots for glyphosate determination based on fluorescence resonance energy transfer and logic gate operation

Herein, a novel method based on fluorescence resonance energy transfer (FRET) between carbon dots (CDs) and glyphosate (Gly) was designed for Gly.detection. CDs were synthesized via a facile and one-step hydrothermal method using citric acid and Tris. The CDs possessed strong blue fluorescence and excitation wavelength-dependent emission behavior with the maximum excitation and emission wavelength at 340nm and 410nm, respectively. However, the presence of glyphosate could effectively quench the fluorescence intensity of the CDs through FRET and this phenomenon has been exploited to design an AND logic gate for sensitively sensing Gly for the first time. Furthermore, the proposed method has been successfully utilized to detect glyphosate in water samples with satisfactory results. The detection limit for glyphosate was 0.6 mu mol L-1(3 sigma/k), with the linear range of 0.02-2.0 mu mol L-1. This is a promising approach for rapid screening of glyphosate in environmental water samples without using any costly instruments. (C) 2016 Elsevier B.V. All rights reserved.