A Novel Cu(Ii)-Assisted Peptide Fluorescent Probe for Highly Sensitive Detection of Glyphosate in Real Samples:Real Application in Test Strips and Smartphone

Abstract

Glyphosate (Glyp) is a kind of organophosphorus herbicide, and its abuse has caused potential harm to the environment and human health. The development of simple and portable instruments for rapid and visual detection of glyphosate presents is a great challenges. Herein, we successfully developed a novel fluorescent probe L with dansyl fluorophore as a fluorescent dye and tetrapeptide (Ala-Ser-Arg-His-NH2) as a recognition group. According to the design, L showed a specific fluorescence quenching response to Cu2+ and forms L-Cu2+ ensemble with molecular ratio of 2:1, and the detection limit was as low as 12.04 nM. Interestingly, L-Cu2+ ensemble as a novel complex probe exhibited a specific fluorescence-enhanced response to glyphosate without interference from other pesticides based on the strong complexation of glyphosate and Cu2+. The detection limits of L-Cu2+ ensemble to glyphosate was calculated as 12.59 nM. Additionally, the results of the sample recovery experiment showed that probe L has good practicability and accuracy in detecting glyphosate. Moreover, test strips was also fabricated to achieve a facile detection of glyphosate pesticide to demonstrate the practical application potential of the probe, as well as it was integrated with smartphone App to detect semi-quantitative glyphosate in field environment under 365 nm ultraviolet lamp.

Keywords: Fluorescent probe, Tetrapeptide, Glyphosate, Real samples, Smartphone