In this work, a bismuth oxide/pencil graphite electrode (Bi₂O₃/PGE)-based ultrasensitive voltammetric sensor is reported for the quantification of the herbicide diuron (DU) in vegetable samples. A HB pencil lead of diameter 2.0 mm was applied to prepare the electrode. Bismuth oxide nanopowder of the size range 1–10 μm was used. The prepared Bi₂O₃/PGE was characterized by different techniques such as energy-dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). A linear calibration curve was plotted in the range of 5.0–160.0 ng mL⁻¹ in a BR buffer (pH 2.5) solution. The sensitivity of the fabricated sensor was calculated to be 2.80 ng mL⁻¹. The suggested sensor indicated higher sensitivity towards the detection of DU in a small-sized whole-tomato sample with 99.9% recovery.

中文翻译：

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用于监测有害除草剂杜伦的氧化铋改性铅笔石墨传感器的制造

在这项工作中，报告了基于氧化铋/铅笔石墨电极（Bi ₂ O ₃ / PGE）的超灵敏伏安传感器，用于对蔬菜样品中的除草剂杜隆（DU）进行定量。使用直径为2.0 mm的HB铅笔芯制备电极。使用尺寸范围为1–10μm的氧化铋纳米粉末。所制备的Bi ₂ O ₃ / PGE通过不同的技术进行表征，例如能量色散X射线（EDX）光谱，扫描电子显微镜（SEM），电化学阻抗谱（EIS）和循环伏安法（CV）。在5.0–160.0 ng mL ^-1范围内绘制线性校准曲线在BR缓冲液（pH 2.5）溶液中。计算得出的传感器的灵敏度为2.80 ng mL ^-1。建议的传感器表明对小尺寸全番茄样品中DU的检测具有更高的灵敏度，回收率达99.9％。