Ma Hongmin, Zhou Jing, Li Yan, Han Tongqian, Zhang Yong, Hu Lihua, Du Bin, Wei Qin
School of Resources and Environment, University of Jinan, Jinan 250022, P. R. China.
School of Resources and Environment, University of Jinan, Jinan 250022, P. R. China.
Biosens Bioelectron. 2016 Jun 15;80:352-358. doi: 10.1016/j.bios.2016.01.069. Epub 2016 Jan 29.
EuPO4 nanowire, which exhibited strong and stable cathodic electrochemiluminescence (ECL) activity, was used for the first time to fabricate an immunosensor for the detection of prostate specific antigen (PSA). EuPO4 has some inherent excellent properties such as long luminescence lifetime, narrow emission band, high quantum yield and low toxicity. Based on these properties, a novel label-free ECL immunosensor was developed using EuPO4 as a sensing matrix. Chitosan solution was used to disperse EuPO4 nanowires and the amino groups on chitosan enabled the covalent attachment of capture antibodies. After the modification of the electrode surface with EuPO4 nanowires, anti-PSA was then immobilized on them, forming a label-free immunosensing interface. The specific binding of PSA on the electrode inhibited the ECL reaction of EuPO4 nanowires with the coreactant due to the steric hindrance effect (Deng et al., 2013). Under the optimum conditions, a good linear relationship between ECL intensity and the logarithm of PSA concentration was obtained in the range of 0.0005-80 ng/mL with a detection limit of 177.33 fg/mL. The proposed ECL immunosensor showed good stability, acceptable selectivity and reproducibility.
具有强而稳定的阴极电化学发光（ECL）活性的EuPO4纳米线首次被用于制备检测前列腺特异性抗原（PSA）的免疫传感器。EuPO4具有一些固有的优异特性，如长发光寿命、窄发射带、高量子产率和低毒性。基于这些特性，开发了一种以EuPO4为传感基质的新型无标记ECL免疫传感器。壳聚糖溶液用于分散EuPO4纳米线，壳聚糖上的氨基能够实现捕获抗体的共价连接。在用EuPO4纳米线修饰电极表面后，将抗PSA固定在其上，形成无标记免疫传感界面。由于空间位阻效应（邓等人，2013年），PSA在电极上的特异性结合抑制了EuPO4纳米线与共反应剂的ECL反应。在最佳条件下，ECL强度与PSA浓度的对数在0.0005-80 ng/mL范围内呈现良好的线性关系，检测限为177.33 fg/mL。所提出的ECL免疫传感器表现出良好的稳定性、可接受的选择性和重现性。
