Institute of Microelectronics, 11 Science Park Road, Singapore Science Park II, 117685 Singapore, Singapore.
Institute of Microelectronics, 11 Science Park Road, Singapore Science Park II, 117685 Singapore, Singapore.
Biosens Bioelectron. 2014 May 15;55:26-31. doi: 10.1016/j.bios.2013.11.070. Epub 2013 Dec 4.
Comb structured gold microelectrode array (CSGMA) functionalized with self-assembled monolayer of thiol terminated coiled-coil peptide (CCP) linked together by the thrombin specific cleavage site (Leu-Val-Pro-Arg-Gly-Ser) has been used to fabricate an ultrasensitive, disposable, electrochemical thrombin biosensor. CCP with thiol at one end provides the ease of CSGMA functionalization and the presence of thrombin specific peptide in the middle of coiled-coil peptide provides site for thrombin capture and detection. CCP/CSGMA electrodes were characterized using label-free electrochemical impedance (EIS) technique and exposed to solutions with different thrombin concentrations for its estimation. Results reveal that CCP/CSGMA electrodes have a limit of detection (LOD) of 10 fg/ml (28 fM) and are able to detect catalytic activity of thrombin within 30 min time frame. CCP/CSGMA electrodes were found to be selective against other IgG anti-bodies such as DO1 and HA. Thus, CCP/CSGMA electrodes provide high specificity toward thrombin detection and mechanistic details of binding and cleavage process.
采用巯基末端自组装卷曲肽（CCP）修饰的组合结构金微电极阵列（CSGMA），其中 CCP 通过凝血酶特异性切割位点（Leu-Val-Pro-Arg-Gly-Ser）连接在一起，用于制备超灵敏、一次性、电化学凝血酶生物传感器。CCP 的一端带有巯基，便于 CSGMA 的功能化，而卷曲肽中间的凝血酶特异性肽为凝血酶的捕获和检测提供了位点。使用无标记电化学阻抗（EIS）技术对 CCP/CSGMA 电极进行了表征，并将其暴露于不同凝血酶浓度的溶液中进行估计。结果表明，CCP/CSGMA 电极的检测限（LOD）为 10 fg/ml（28 fM），能够在 30 分钟的时间内检测到凝血酶的催化活性。CCP/CSGMA 电极对其他 IgG 抗体（如 DO1 和 HA）具有选择性。因此，CCP/CSGMA 电极对凝血酶检测具有高特异性，并且能够提供结合和切割过程的机制细节。
