Yuan Ruo, Tang Dianping, Chai Yaqin, Zhong Xia, Liu Yan, Dai Jianyuan
Chong Qing Key Laboratory of Analytical Chemistry, College of Chemistry and Chemical Engineering, Southwest China Normal University, Chongqing 400715, China.
Langmuir. 2004 Aug 17;20(17):7240-5. doi: 10.1021/la030428m.
A novel potentiometric immunosensor for detection of hepatitis B surface antigen (HBsAg) has been developed by means of self-assembly (SA) and opposite-charged adsorption (OCA) techniques to immobilize hepatitis B surface antibody (HBsAb) on a platinum electrode. A cleaned platinum electrode was first pretreated in the presence of 10% HNO3 and 2.5% K2CrO4 solution and held at -1.5 V (vs SCE) for 1 min to make it negatively charged and then immersed in a mixing solution containing hepatitis B surface antibody, colloidal gold (Au), and polyvinyl butyral (PVB). Finally, HBsAb was successfully immobilized onto the surface of the negatively charged platinum electrode modified nanosized gold and PVB sol-gel matrixes. The modified procedure was characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The immobilized hepatitis B surface antibody exhibited direct electrochemical behavior toward hepatitis B surface antigen (HBsAg). The performance and factors influencing the performance of the resulting immunosensor were studied in detail. More than 95.7% of the results of the human serum samples obtained by this method were in agreement with those obtained by enzyme-linked immunosorbent assays (ELISAs). The resulting immunosensor exhibited fast potentiometric response (<3 min) to HBsAg. The detection limit of the immunosensor was 2.3 ng.mL(-1), and the linear range was from 8 to 1280 ng.mL(-1). Moreover, the studied immunosensor exhibited high sensitivity, good reproducibility, and long-term stability (>6 months).
一种用于检测乙型肝炎表面抗原（HBsAg）的新型电位免疫传感器已通过自组装（SA）和异电荷吸附（OCA）技术开发出来，用于将乙型肝炎表面抗体（HBsAb）固定在铂电极上。首先将清洁后的铂电极在10%硝酸和2.5%铬酸钾溶液中进行预处理，并在-1.5 V（相对于饱和甘汞电极）下保持1分钟，使其带负电荷，然后浸入含有乙型肝炎表面抗体、胶体金（Au）和聚乙烯醇缩丁醛（PVB）的混合溶液中。最后，HBsAb成功固定在带负电荷的铂电极表面修饰的纳米金和PVB溶胶-凝胶基质上。通过电化学阻抗谱（EIS）和循环伏安法（CV）对修饰过程进行了表征。固定化的乙型肝炎表面抗体对乙型肝炎表面抗原（HBsAg）表现出直接电化学行为。详细研究了所得免疫传感器的性能及影响其性能的因素。用该方法获得的人血清样本结果中，超过95.7%与酶联免疫吸附测定（ELISA）结果一致。所得免疫传感器对HBsAg表现出快速的电位响应（<3分钟）。该免疫传感器的检测限为2.3 ng.mL(-1)，线性范围为8至1280 ng.mL(-1)。此外，所研究的免疫传感器具有高灵敏度、良好的重现性和长期稳定性（>6个月）。
