Li Wei, Wu Hongqi, Wu Cong, Jiao Peidong, Xu Ling, Song Haiyan
College of Agricultural Engineering, Shanxi Agricultural University, Taigu, 030801, China; Dryland Farm Machinery Key Technology and Equipment Key Laboratory of Shanxi Province, Taigu, 030801, China.
College of Agricultural Engineering, Shanxi Agricultural University, Taigu, 030801, China.
Talanta. 2025 May 1;286:127530. doi: 10.1016/j.talanta.2025.127530. Epub 2025 Jan 10.
This study introduces an innovative electrochemical biosensor, engineered through the functionalization screen-printed electrode (SPE) with a coordination complex comprised of 4-mercaptobenzoic acid (4-MBA) and copper ions (Cu), achieving precise quantitative determination of glyphosate. Electrodepositing gold nanoparticles (AuNPs) onto the electrode surface, forming a self-assembled monolayer (SAM) of 4-MBA via thiol-gold interactions, and immobilizing Cu via coordination bonding with the monolayer, finalizing the electrochemical biosensor construction as Cu/4-MBA/AuNPs/SPE. The successful modification of the biosensor interface is confirmed through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and electrochemical characterization. Through parameter optimization, critical metrics for the biosensor preparation process have been determined. Using square wave voltammetry (SWV), a linear relationship between the glyphosate concentration and the peak current inhibition ratio at the electrode surface is established. Additionally, the repeatability and anti-interference capabilities of the fabricated biosensors are evaluated. The experimental outcomes affirm the biosensor's capability for quantitative glyphosate detection across a 5-100 nM range, boasting a 1.65 nM limit of detection (LOD). Testing on tap water samples verifies a robust recovery rate for glyphosate residues, spanning 89.84 %-107.48 %. The proposed biosensor holds significant promise for glyphosate detection, offering substantial applicability and this study provides a valuable reference for the advancement of biosensors geared toward the quantitative assessment of organophosphate pesticides (OPs).
本研究介绍了一种创新的电化学生物传感器，该传感器通过用由4-巯基苯甲酸（4-MBA）和铜离子（Cu）组成的配位络合物对丝网印刷电极（SPE）进行功能化处理而构建，实现了对草甘膦的精确定量测定。将金纳米颗粒（AuNPs）电沉积到电极表面，通过硫醇-金相互作用形成4-MBA的自组装单分子层（SAM），并通过与该单分子层的配位键固定Cu，最终构建成Cu/4-MBA/AuNPs/SPE电化学生物传感器。通过扫描电子显微镜（SEM）、能量色散X射线光谱（EDX）和电化学表征证实了生物传感器界面的成功修饰。通过参数优化，确定了生物传感器制备过程的关键指标。使用方波伏安法（SWV），建立了草甘膦浓度与电极表面峰电流抑制率之间的线性关系。此外，还评估了所制备生物传感器的重复性和抗干扰能力。实验结果证实了该生物传感器在5-100 nM范围内定量检测草甘膦的能力，检测限（LOD）为1.65 nM。对自来水样品的测试验证了草甘膦残留的回收率很高，范围为89.84%-107.48%。所提出的生物传感器在草甘膦检测方面具有巨大潜力，具有广泛的适用性，本研究为推进用于有机磷农药（OPs）定量评估的生物传感器提供了有价值的参考。
