title: Electrochemical impedance immunosensor for sub-picogram level detection of bovine interferon gamma based on cylinder-shaped TiO₂ nanorods.
abstract: Bovine interferon gamma (BoIFN-γ) released by T cells plays very important roles in early diagnosis of Mycobacterium tuberculosis (MTB) infections and control of bovine tuberculosis. In this work, a label-free electrochemical impedance immunosensor is for the first time developed for highly sensitive determination of BoIFN-γ. Cylinder-shaped TiO2 nanorods are synthesized by a facile hydrothermal method, and show high surface area and good hydrophicility. The immunosensor is fabricated by the immobilization of BoIFN-γ monoclonal antibody on the TiO2 nanorods modified glassy carbon electrode. The prepared TiO2 and immunosensor are characterized using transmission electron microscopy, scanning electron microscopy, X-ray diffraction, contact angle measurement, cyclic voltammetry, and electrochemical impedance spectra. The BoIFN-γ concentration is measured through the relative increase of impedance values in corresponding specific binding of BoIFN-γ antigen and BoIFN-γ antibody. The relative increased impedance values are proportional to the logarithmic value of BoIFN-γ concentrations in a wide range of 0.0001 to 0.1 ng/mL with a low detection limit of 0.1 pg/mL. The developed BoIFN-γ immunosensor shows a 249-fold decrease in detection limit in comparison with current enzyme-linked immunosorbent assay. This study provides a new, simple, and highly sensitive approach for very potential application in early diagnosis of MTB infections and control of bovine tuberculosis.
authors.affiliation: Jiangsu Key Laboratory of Environmental Material and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China. Electronic address: zjyang@yzu.edu.cn.
authors.forename: Zhanjun
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Jiangsu Key Laboratory of Environmental Material and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China.
authors.forename: Zhiqin
authors.initials: Z
authors.lastname: Jian
authors.affiliation: Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225002, PR China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Chen
authors.affiliation: Jiangsu Key Laboratory of Environmental Material and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory of Environmental Material and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China.
authors.forename: Piya
authors.initials: P
authors.lastname: Qin
authors.affiliation: Jiangsu Key Laboratory of Environmental Material and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225002, PR China.
authors.forename: Xin'an
authors.initials: X
authors.lastname: Jiao
authors.affiliation: Jiangsu Key Laboratory of Environmental Material and Environmental Engineering, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China. Electronic address: xyhu@yzu.edu.cn.
authors.forename: Xiaoya
authors.initials: X
authors.lastname: Hu
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000276:immunology; D015374:Biosensing Techniques / Q000295:instrumentation; D002417:Cattle / Q000097:blood* / Q000276:immunology; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation*; D007371:Interferon-gamma / Q000097:blood* / Q000276:immunology; D008832:Microchemistry / Q000295:instrumentation*; D008968:Molecular Conformation; D043942:Nanotubes / Q000737:chemistry / Q000648:ultrastructure; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014025:Titanium / Q000737:chemistry*
chemical_list: D000911:Antibodies, Monoclonal; C009495:titanium dioxide; D007371:Interferon-gamma; D014025:Titanium
keywords: Bovine interferon gamma; Cylinder-shaped TiO(2); Cytokine; Electrochemical impedance immunosensor; Label-free; nanorods