Abstract Electrochemical sensor based on glassy carbon electrode modified with asolectin (mixture of soybean phospholipids) was developed. Properties of phospholipid layer, such as thickness and compactness, were investigated using atomic force microscopy and X-ray photoelectron spectroscopy. Phospholipids completely cover whole surface and the thickness of the layer 7.1 ± 1.2 nm corresponds to the value of the phospholipid bilayer of cell membranes. Due to the accumulation of paraquat in the phospholipid layer, square wave voltammetry with asolectin modified electrode exhibits three times higher sensitivity, measured as a slope of calibration dependence, and better linearity in comparison to unmodified glassy carbon electrode. Limit of detection 2.2 nmol L−1 and recoveries higher than 88% were achieved in model samples of water. The method was used for determination of paraquat in real sample of river water and results were compared with high performance liquid chromatography and differential pulse voltammetry on hanging mercury drop electrode giving 0.071 ± 0.010, 0.050 ± 0.010 and 0.061 ± 0.008 μmol L−1, respectively.

中文翻译：

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基于磷脂修饰玻碳电极的电化学传感器——百草枯的测定

摘要 研制了基于大豆凝集素（大豆磷脂混合物）修饰的玻碳电极的电化学传感器。使用原子力显微镜和 X 射线光电子能谱研究了磷脂层的特性，例如厚度和致密性。磷脂完全覆盖整个表面，7.1 ± 1.2 nm 层的厚度对应于细胞膜磷脂双层的值。由于百草枯在磷脂层中的积累，与未修饰的玻碳电极相比，使用 asolectin 修饰电极的方波伏安法表现出高三倍的灵敏度（以校准依赖性斜率测量）和更好的线性。在水的模型样品中实现了 2.2 nmol L-1 的检测限和高于 88% 的回收率。