基于Au-g-C3N4 NS纳米复合材料的分子印迹电化学发光传感器检测叶酸

近年来,作为一种新型的二维半导体纳米材料,石墨相氮化碳纳米薄片（g-C₃N₄ NS）因其优异的电化学发光（ECL）性能和良好的成膜特性在ECL传感领域备受关注。然而,g-C₃N₄ NS在较高的工作电压下产生的ECL信号不稳定,而金纳米粒子（Au NPs）的引入可明显改善其发光稳定性. 基于这个特点,采用原位生长法将Au NPs引入g-C₃N₄ NS中,制备了一种金-石墨相氮化碳纳米复合材料（Au-g-C₃N₄ NS）,以其作为ECL物质固定在电极上. 同时,引入具有专一识别能力的分子印迹聚合物（MIP）,构建了一种检测叶酸（FA）的分子印迹-电化学发光（MIP-ECL）传感器. 该传感器对FA表现出良好的选择性和灵敏响应,在优化的条件下,信号变化与FA物质的量浓度在1.0×10^-10~1.0×10^-3 mol·L^-1的范围内呈良好的线性关系,检出限（LOD）达到0.07 nmol·L^-1. 并且探讨了检测机理,考察了传感器的稳定性和重现性,将传感器用于实际样品中FA的检测,获得满意结果.

A molecule-imprinted electrochemiluminescence sensor based on Au-g-C3N4 NS nanocomposite for detection of folic acid

As a new type of two-dimensional semiconductor nanomaterials, graphite-phase carbon nitride nanosheets（g-C₃N₄ NS） have attracted much attention in the field of electrochemiluminescence（ECL） sensing due to their excellent ECL performance and excellent film forming properties. However, the ECL signal generated by g-C₃N₄ NS is unstable at higher operating voltages. The introduction of gold nanoparticles（Au NPs） can significantly improve the luminescence stability. Accordingly, Au NPs were introduced into g-C₃N₄ NS through in situ growth to obtain Au-g-C₃N₄ NS which was fixed on the electrode as the ECL substance. Meanwhile, a molecularly imprinted polymer（MIP） with specific recognition ability was introduced to construct a MIP-ECL sensor for detecting folic acid （FA）. The sensor showed a high selectivity and sensitivity to FA. The ECL signal showed a good linear relationship with FA concentration in the range of 1.0×10^-10-1.0×10^-3 mol·L^-1, and the limit of detection（LOD） was 0.07 nmol·L^-1. The sensor was used to detect folic acid in the samples, and satisfactory results were obtained.