title: An impedance array biosensor for detection of multiple antibody-antigen interactions.
abstract: Electrochemical impedance spectroscopy (EIS) combined with a gold electrode array was developed to detect multiple antibody-antigen interactions. Hepatitis B surface antigen (HBsAg), as a model sample, was employed to evaluate the characteristics of the biosensor. The array was fabricated by immobilizing antibodies on the self-assembled molecules surface of the electrodes. The surface characteristics of the array during the binding process including the antibody-antigen conjugation and the sandwich complex with HRP-labeled antibody, as well as the precipitation layer, were characterized by atomic force microscopy (AFM) and electrochemical impedance spectroscopy, respectively. A linear relationship between electron-transfer resistance and the concentrations of HBsAg ranged from 10 pg ml(-1) to 1 ng ml(-1) and the detection limit of 10 pg ml(-1) was obtained. 100 pg ml(-1) antigen samples, such as rat IgG, HBsAg and HBeAg, as well as the antigen mixture, were incubated with the relative antibody-modified electrodes on the array. No obvious cross-talk reaction was observed. All these results confirm the feasibility of applying electrochemical impedance spectroscopy to the electrode array.
authors.affiliation: College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Yu
authors.forename: Renji
authors.initials: R
authors.lastname: Lv
authors.forename: Zhenqiu
authors.initials: Z
authors.lastname: Ma
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Liu
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Hao
authors.forename: Qingzhang
authors.initials: Q
authors.lastname: Li
authors.forename: Danke
authors.initials: D
authors.lastname: Xu
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D015374:Biosensing Techniques; D017097:Electric Impedance; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D006046:Gold; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D006513:Hepatitis B e Antigens / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D051381:Rats
chemical_list: D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens; D007074:Immunoglobulin G; D006046:Gold