Zhong Tong-Sheng, Liu Guodong
Department of Chemistry and Environmental Engineering, Hunan City College, Yiyang 413049, P R China.
Anal Sci. 2004 Mar;20(3):537-41. doi: 10.2116/analsci.20.537.
An amperometric immunosensor was constructed by dispersing graphite, schistosoma-japonicum antigen (SjAg) and silica sol-gel at low temperature. The performance characteristics of the prepared immunosensor were examined in the buffered solution of o-aminophenol (o-AP) used as a substrate. It exhibited excellent physical and electrochemical stability with a renewable external surface. A competitive binding assay was employed to determine schistosoma-japonicum antibody (SjAb) with the aid of horseradish peroxidase labeled SjAb (HRP-SjAb). The experimental parameters for SjAb assay were optimized, including the amount of labeled SjAb in incubation solution, incubation time, temperature and the pH of solution. The use of o-AP substrate and amperometric detection at -250 mV (vs. SCE) results in a determination limit of 0.32 microg/ml and a linear range extending up to 0.18 microg/ml. The results of SjAb assay in serum samples demonstrate the feasibility of using the proposed immunosensor for clinical analysis.
通过在低温下分散石墨、日本血吸虫抗原（SjAg）和硅溶胶 - 凝胶构建了一种安培免疫传感器。在用作底物的邻氨基酚（o - AP）缓冲溶液中检测所制备免疫传感器的性能特征。它具有可再生的外表面，表现出优异的物理和电化学稳定性。采用竞争结合测定法，借助辣根过氧化物酶标记的日本血吸虫抗体（HRP - SjAb）来测定日本血吸虫抗体（SjAb）。对SjAb测定的实验参数进行了优化，包括孵育溶液中标记SjAb的量、孵育时间、温度和溶液的pH值。使用o - AP底物并在 - 250 mV（相对于饱和甘汞电极）下进行安培检测，测定限为0.32微克/毫升，线性范围扩展至0.18微克/毫升。血清样本中SjAb测定的结果证明了使用所提出的免疫传感器进行临床分析的可行性。
