Detection of Saccharomyces cerevisiae immobilized on self-assembled monolayer (SAM) of alkanethiolate using electrochemical impedance spectroscopy
Detection of Saccharomyces cerevisiae immobilized on self-assembled monolayer (SAM) of alkanethiolate using electrochemical impedance spectroscopy
复制标题
DOI：
10.1016/j.aca.2005.08.086
复制
发表时间：
2005-12-04
影响因子：
6.2
通讯作者：
Tan, SN
中科院分区：
文献类型：
--
作者：
Chen, H;Heng, CK;Tan, SN
化学功能化自组装单分子膜(SAM)的制备在酶、DNA、全细胞等生物活性物种的固定化方面具有重要的应用价值。原子力显微镜(AFM)和光学显微镜分别清晰地观察到3-巯基丙酸(MPA)单分子膜组装和酵母细胞固定化后在金电极表面形成的图案。电化学阻抗谱(EIS)测量是基于[Fe(CN)(6)](3-/4-)氧化还原对的电荷转移动力学。SAM的组装和酵母细胞随后在金电极上的固定大大增加了氧化还原对的电子转移电阻(R-Et)，降低了双电层电容(C-dl)。在10(2)~10(8)cfu mL(-1)范围内，R-ET与酵母菌浓度对数值呈线性关系。(C)2005 Elsevier B.V.保留所有权利。
The preparation of chemically functionalized self-assembled monolayer (SAM) surfaces is of great interest for applications in the immobilization of various bioactive species such as enzymes, DNA, whole cells, etc. In this paper, an electrochemical impedance biosensor for the rapid detection of Saccharomyces cerevisiae (yeast cells) was developed by immobilizing yeast cells on a gold surface modified with an alkanethiolate SAM. The patterns formed on the gold electrode surface after the assembly of 3-mercaptopropionic acid (MPA) monolayer and the immobilization of yeast cells were clearly observed from atomic force microscopy (AFM) and optical microscope, respectively. The electrochemical impedance spectroscopy (EIS) measurements were based on the charge-transfer kinetics of [Fe(CN)(6)](3-/4-) redox couple. The SAM assembly and the subsequent immobilization of yeast cells on the gold electrodes greatly increased the electron-transfer resistance (R-et) of the redox couple and decreased the double layer capacitance (C-dl). A linear relationship between the R-et and logarithmic value of yeast concentrations was found in the range between 10(2) and 10(8) cfu mL(-1). (c) 2005 Elsevier B.V. All rights reserved.