A 3D-impedimetric immunosensor based on foam Ni for detection of sulfate-reducing bacteria

Key Lab of Corrosion Science, Shandong Province, Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China; Graduate School of the Chinese Academy of Sciences, 19 (Jia) Yuquan Road, Beijing 100039, China
Electrochemistry Communications 01/2010; DOI: 10.1016/j.elecom.2009.12.017

ABSTRACT A 3D-immunosensor based on simple and efficient trapping platform (foam Ni) combining with adsorption of gold nanoparticles and specific recognition of biological/chemical molecular has been reported for detection of sulfate-reducing bacteria (SRB) using electrochemical impedance spectroscopy (EIS). The impedance spectra were also used to characterize the successful construct and stepwise modification of the impedimetric immunosensors. This results show that a linear relationship between electron-transfer resistance (Rct) values and the logarithm of the SRB concentrations was obtained for the SRB concentration range of 2.1 × 101–2.1 × 107 cfu/ml. Additionally, the fabricated immunosensor shows a high selectivity against other bacteria.

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