Yu Wenlong, Sang Yaxin, Wang Tianying, Liu Weihua, Wang Xianghong
Faculty of Food Science and Technology Agricultural University of Hebei Baoding China.
Food Sci Nutr. 2020 Jan 9;8(2):1001-1011. doi: 10.1002/fsn3.1382. eCollection 2020 Feb.
In this study, a sensitive and selective electrochemical immunosensor for cephalexin (CEX) determination on a glassy carbon electrode (GCE) surface was modified by a carboxylated single-walled carbon nanotubes/chitosan (SWNTs-COOH/CS) composite. The SWNTs-COOH/CS composite was used to enhance sensor performance and to enlarge the electrochemical response of CEX. The cephalosporin-ovalbumin coupling (CEX-OVA) was synthesized using the reactive ester method. The free CEX in solution could be effectively measured based on the competitive immunoreaction between CEX-antibody and CEX. Under optimal conditions, the electrochemical immunosensor offered an excellent response for CEX. The linear range was 1-800 ng/ml, with a detection limit of 45.7 ng/ml ( = 3). This method was applied to determine CEX in six different samples and obtained the recovery range from 80.15% to 94.04%. These results indicated that the fabricated electrochemical immunosensor and sensing method are suitable for quantification of CEX in real samples. These have great potential for wider applications in environmental and agri-food products industries.
在本研究中，一种用于在玻碳电极（GCE）表面测定头孢氨苄（CEX）的灵敏且具有选择性的电化学免疫传感器，通过羧基化单壁碳纳米管/壳聚糖（SWNTs-COOH/CS）复合材料进行了修饰。SWNTs-COOH/CS复合材料用于提高传感器性能并增强CEX的电化学响应。采用活性酯法合成了头孢菌素-卵清蛋白偶联物（CEX-OVA）。基于CEX抗体与CEX之间的竞争性免疫反应，可有效测定溶液中的游离CEX。在最佳条件下，该电化学免疫传感器对CEX具有出色的响应。线性范围为1-800 ng/ml，检测限为45.7 ng/ml（n = 3）。该方法应用于六种不同样品中CEX的测定，回收率范围为80.15%至94.04%。这些结果表明，所制备的电化学免疫传感器和传感方法适用于实际样品中CEX的定量分析。它们在环境和农业食品工业中具有更广泛应用的巨大潜力。
