Electrochemical luminescence sensor based on double suppression for highly sensitive detection of glyphosate

• Published in: Sensors and actuators. B, Chemical Chemical, 2020-02, Vol.304, p.127364, Article 127364
• Main Authors: Liu, Hanbiao, Chen, Peipei, Liu, Zhen, Liu, Jianhui, Yi, Jiangle, Xia, Fangquan, Zhou, Changli
• Format: Article
• Language: English
• Subjects: Copper; Cysteine; Double inhibition; Electrochemiluminescence; Electrochemiluminescence sensor; Enzyme; Glyphosate; Gold; Hydrogen peroxide; Luminescence; Nanoparticles; Peroxidase; Reagents; Selectivity; Sensors
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2019.127364

•The synthesized luminol-Au-L-cys-Cu(II) composite has dual functions of luminescence and peroxidase-like.•The double inhibition strategy increased the sensitivity of glyphosate detection.•The constructed ECL sensor showed high specificity and good reproducibility. An electrochemical luminescence sensor based on a double inhibition strategy for the detection of glyphosate was constructed. In this method, the luminol-gold nanoparticles-L-cysteine-Cu(II) composites (Lu-Au-Lcys-Cu(II)) were used as luminescent reagents, and H2O2 obtained from two-step enzymatic hydrolysis reaction was used as the co-reactive agent of Lu-Au-Lcys-Cu(II). Glyphosate could inhibit the enzymatic reaction, and inhibit catalytic action of the peroxidase-mimicking by competing with L-cysteine to form a complex of glyphosate-Cu(II). The electrochemical luminescence intensity decreased with the increase of glyphosate concentration, under the optimal conditions, the linear range of glyphosate concentration was 0.001 ∼ 1.0 μM, and the limit of detection (LOD) could be as low as 0.5 nM. Importantly, the Electrochemiluminescence sensor also showed acceptable stability and selectivity.