Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic.
Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic.
Talanta. 2018 May 15;182:111-115. doi: 10.1016/j.talanta.2018.01.054. Epub 2018 Jan 31.
A novel enzyme-free electrochemical immunosensor was developed for highly sensitive detection and quantification of human epididymis protein 4 (HE4) in human serum. For the first time, core/shell CdSe/ZnS quantum dots were conjugated with anti-HE4 IgG antibodies for subsequent sandwich-type immunosensing with superparamagnetic microparticles functionalized with anti-HE4 IgG antibodies, which allow rapid and efficient HE4 capture from the sample. Electrochemical detection of anti-HE4 IgG - HE4 - anti-HE4 IgG immunocomplex was performed by recording the current response of Cd(II) ions, released from dissolved quantum dots at screen-printed carbon electrode (SPCE), modified with mercury or bismuth film. The linear range of the detection was from 20 pM to 40 nM with limit of detection of 12 pM using three times the standard deviation of blank criterion at mercury-film SPCE and from 100 pM to 2 nM with limit of detection of 89 pM at bismuth-film SPCE. Proposed electrochemical immunosensor meets the requirements for fast and sensitive quantification of HE4 biomarker in early stage of ovarian cancer and due to the proper sensitivity and specificity presents a promising alternative to enzyme-based probes used routinely in clinical diagnostics.
一种新型的无酶电化学免疫传感器被开发用于在人血清中高度灵敏地检测和定量人附睾蛋白 4（HE4）。首次将核壳型 CdSe/ZnS 量子点与抗 HE4 IgG 抗体偶联，随后与超顺磁性微粒进行三明治型免疫反应，超顺磁性微粒通过抗 HE4 IgG 抗体功能化，可以从样品中快速有效地捕获 HE4。通过记录溶解的量子点在汞或铋修饰的丝网印刷碳电极（SPCE）上释放的 Cd(II) 离子的电流响应来进行电化学检测抗-HE4 IgG-HE4-抗-HE4 IgG 免疫复合物。使用汞膜 SPCE 时，检测范围为 20 pM 至 40 nM，检出限为 12 pM，三倍空白标准偏差；使用铋膜 SPCE 时，检测范围为 100 pM 至 2 nM，检出限为 89 pM。所提出的电化学免疫传感器满足快速灵敏检测卵巢癌早期 HE4 生物标志物的要求，由于适当的灵敏度和特异性，为临床诊断中常用的基于酶的探针提供了有前途的替代方案。
