Assessment of the interaction between a synthetic epitope of troponin C and its specific antibody using a label-free faradaic impedimetric immunosensor and alpha-Keggin silicotungstic heteropolyacid as a redox probe

作者：Mantzila Aikaterini G; Strongylis Constantinos; Tsikaris Vassihos; Prodromidis Mamas I^*

来源：Biosensors and Bioelectronics, 2007, 23(3): 362-369.

DOI：10.1016/j.bios.2007.04.017

• faradaic impedimetric immunosensor
• silicotungstic heteropolyacid
• electrochemical impedance spectroscopy
• synthetic peptide
• troponin c

The development of an immunosensor for the direct probing of the interaction between a cysteine-modified synthetic peptide, which corresponds to the epitope cTnC-89-98 of troponin C, and its specific antibody is described. Following immobilization of the peptide onto gold electrodes through the formation of a self-assembled monolayer, the alteration of the interfacial properties of the electrodes upon peptide-antibody interaction was traced by faradaic electrochemical impedance spectroscopy (EIS) using a silicotungstic heteropolyacid, H(4)SiO(4)(.)12WO(3), as a redox probe. The electrochemical behaviour of the redox probe was evaluated with cyclic voltammetry and EIS. The effect of milk protein or 4-mercaptophenol, which was used as post-blocking agents, on the performance of the immunosensor, was investigated. Treatment with 4-mercaptophenol resulted in immunoeffective electrodes that successfully tested in anti-serum samples. An optimum dilution ratio of the samples, where the effect of the matrix on the measuring signal is negligible, was also determined.

• 出版日期2007-10-31