Sm3+-tuning aggregation-induced emission of copper nanoclusters for sensitive and visual detection of glyphosate

Organophosphorus pesticides (OPs) are commonly employed in agriculture because they effectively control pests and increase crop output. However, most OPs are highly toxic. As a result, precise detection of OPs residues is critical for monitoring human disease and protecting the environment. In this work, we developed an aggregation-induced emission (AIE) probe of Sm-GSH-CuNCs for sensitive and visual detection of OPs by combining Sm 3+ with glutathione-modified copper nanoclusters (GSH-CuNCs). Using glyphosate as the OPs model, the fluorescence of GSH-CuNCs was quenched due to the stronger affinity between Sm 3+ and glyphosate than that between Sm 3+ and GSH-CuNCs, as well as the formation of new P-O-Sm bonds between Sm 3+ and glyphosate , resulting in the "on-off" response of the AIE probe. The Sm-GSH-CuNCs probe detected glyphosate throughout a linear range of 0.338–5.070 mg/L, with a detection limit of 0.013 mg/L. Furthermore, we have constructed an Sm-GSH-CuNCs agar slice detection platform that used smartphone assistance to detect glyphosate visually and quantitatively. A good linear relationship between R/B values and OPs concentrations( C i ) was discovered: R/B =-0.316  C i +1.943 ( R 2 =0.9970). This work provided a simple, low-cost, and portable detection method for quantifying or visualizing OPs.