Lee Seung-Jun, Anandan Venkataramani, Zhang Guigen
Micro/Nano Bioengineering Laboratory, Department of Biological and Agricultural Engineering, The University of Georgia, Athens, GA 30602, USA.
Biosens Bioelectron. 2008 Feb 28;23(7):1117-24. doi: 10.1016/j.bios.2007.10.025. Epub 2007 Nov 4.
Bioaffinity sensors need to be rapid, specific, and highly sensitive. To realize these features, electrodes that can elicit high electrochemical performance are necessary. In this study, we developed nanorod array electrode and performed cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) experiments to study the interfacial properties of the nanorod array electrode with Fe(CN)(6)(3-/4-) as the redox molecules. Results showed that both the CV and EIS measurements captured very well the resistive and capacitive changes due to the adsorption of functionalizing molecules and the coupling between avidin and biotin. The EIS measurements were more sensitive in discriminating small changes caused by the surface adsorption of various molecules. The use of avidin-functionalized gold nanorod modified electrodes had led to much increased detection sensitivity along with a detection-limit as low as 1 ng/mL of biotin.
生物亲和传感器需要具备快速、特异性强和高灵敏度的特点。为实现这些特性，需要能够产生高电化学性能的电极。在本研究中，我们开发了纳米棒阵列电极，并进行了循环伏安法（CV）和电化学阻抗谱（EIS）实验，以研究以铁氰化物（Fe(CN)(6)(3-/4-)）作为氧化还原分子时纳米棒阵列电极的界面性质。结果表明，CV和EIS测量都很好地捕捉到了由于功能化分子吸附以及抗生物素蛋白与生物素之间的偶联而引起的电阻和电容变化。EIS测量在区分各种分子表面吸附引起的微小变化方面更为灵敏。使用抗生物素蛋白功能化的金纳米棒修饰电极使得检测灵敏度大幅提高，生物素的检测限低至1 ng/mL。
