title: Silver nanowire-based electrochemical immunoassay for sensing immunoglobulin G with signal amplification using strawberry-like ZnO nanostructures as labels.
abstract: The quick development of nanoscience and nanotechnology has paved the way for ultrasensitive biosensing and analysis. In this work, an ultrasensitive electrochemical immunosensor was developed for the detection of human immunoglobulin G (IgG) by combining with a newly designed trace tag on a disposable immunosensor array. The array was prepared by immobilizing captured antibodies on ultralong Ag nanowires, whilst the trace tag was prepared by loading horseradish peroxidase (HRP)-labeled goat anti-human IgG (HRP-anti-IgG) on thionine (TH)-doped mesoporous ZnO nanostrawberries (MP-ZnO). With a sandwich-type immunoassay format, mainly due to crystalline framework and high surface area of the mesoporous (MP) materials, as well as the superconductivity of silver nanowires, the electrochemical signal was significantly amplified. The linear range of the developed immunosensor is 0.01-200 ng mL(-1) and the detection limit is 4 pg mL(-1) IgG, which make the hierarchically nanostructured composites very promising candidates for the next-generation sandwich-type electrochemical immunoassays.
authors.affiliation: School of Biochemical and Pharmaceutical Sciences, Capital Medical University, Beijing 100069, China. caoxia@ccmu.edu.cn
authors.forename: Xia
authors.initials: X
authors.lastname: Cao
authors.forename: Shangwei
authors.initials: S
authors.lastname: Liu
authors.forename: Quanchen
authors.initials: Q
authors.lastname: Feng
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007074:Immunoglobulin G / Q000032:analysis*; D057230:Limit of Detection; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D012834:Silver / Q000737:chemistry*; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D007074:Immunoglobulin G; D012834:Silver; D015034:Zinc Oxide
keywords: Ag nanowires; Electrochemical immunoassay; IgG; Mesoporous ZnO nanostrawberries