Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, PR China.
Biosens Bioelectron. 2011 Jan 15;26(5):2297-303. doi: 10.1016/j.bios.2010.09.056. Epub 2010 Oct 8.
Successful development of an ultrasensitive and highly specific electrochemical aptasensor for thrombin based on amplification of aptamer-gold nanoparticles-horseradish peroxidase (aptamer-AuNPs-HRP) conjugates was reported. In this electrochemical protocol, aptamer1 (Apt1) was immobilized on core/shell Fe(3)O(4)/Au magnetic nanoparticles (AuMNPs) and served as capture probe. Aptamer2 (Apt2) was dual labeled with AuNPs and HRP and used as detection probe. In the presence of thrombin, the sandwich format of AuMNPs-Apt1/thrombin/Apt2-AuNPs-HRP was fabricated. Remarkable signal amplification was realized by taking the advantage of AuNPs and catalytic reactions of HRP. Other proteins, such as human serum albumin, lysozyme, fibrinogen, and IgG did not show significant interference with the assay for thrombin. Linear response to thrombin concentration in the range of 0.1-60 pM and lower detection limit down to 30 fM (S/N=3) was obtained with the proposed method. This electrochemical aptasensor is simple, rapid (the whole detection period for a thrombin sample is less than 35 min), sensitive and highly specific, it shows promising potential in protein detection and disease diagnosis.
成功开发了一种基于适配体-金纳米粒子-辣根过氧化物酶（aptamer-AuNPs-HRP）缀合物放大的超灵敏和高度特异的电化学适体传感器用于检测凝血酶。在该电化学方案中，将适配体 1（Apt1）固定在核/壳 Fe(3)O(4)/Au 磁性纳米颗粒（AuMNPs）上作为捕获探针。适配体 2（Apt2）双重标记有 AuNPs 和 HRP 并用作检测探针。在凝血酶存在下，制备了 AuMNPs-Apt1/凝血酶/Apt2-AuNPs-HRP 的三明治结构。利用 AuNPs 和 HRP 的催化反应实现了显著的信号放大。其他蛋白质，如人血清白蛋白、溶菌酶、纤维蛋白原和 IgG，对凝血酶的测定没有显示出明显的干扰。该方法对凝血酶浓度在 0.1-60 pM 范围内呈现线性响应，检测下限低至 30 fM（S/N=3）。这种电化学适体传感器简单、快速（凝血酶样品的整个检测时间小于 35 分钟）、灵敏且特异性高，在蛋白质检测和疾病诊断方面显示出有前景的应用潜力。
