title: Nanoporous gold supported cobalt oxide microelectrodes as high-performance electrochemical biosensors.
abstract: Tremendous demands for electrochemical biosensors with high sensitivity and reliability, fast response and excellent selectivity have stimulated intensive research on developing versatile materials with ultrahigh electrocatalytic activity. Here we report flexible and self-supported microelectrodes with a seamless solid/nanoporous gold/cobalt oxide hybrid structure for electrochemical nonenzymatic glucose biosensors. As a result of synergistic electrocatalytic activity of the gold skeleton and cobalt oxide nanoparticles towards glucose oxidation, amperometric glucose biosensors based on the hybrid microelectrodes exhibit multi-linear detection ranges with ultrahigh sensitivities at a low potential of 0.26 V (versus Ag/AgCl). The sensitivity up to 12.5 mA mM⁻¹ cm⁻² with a short response time of less than 1 s gives rise to ultralow detection limit of 5 nM. The outstanding performance originates from a novel nanoarchitecture in which the cobalt oxide nanoparticles are incorporated into pore channels of the seamless solid/nanoporous Au microwires, providing excellent electronic/ionic conductivity and mass transport for the enhanced electrocatalysis.
authors.affiliation: Key Laboratory of Automobile Materials, Ministry of Education, and School of Materials Science and Engineering, Jilin University, Changchun 130022, China.
authors.forename: Xing-You
authors.initials: XY
authors.lastname: Lang
authors.forename: Hong-Ying
authors.initials: HY
authors.lastname: Fu
authors.forename: Chao
authors.initials: C
authors.lastname: Hou
authors.forename: Gao-Feng
authors.initials: GF
authors.lastname: Han
authors.forename: Ping
authors.initials: P
authors.lastname: Yang
authors.forename: Yong-Bing
authors.initials: YB
authors.lastname: Liu
authors.forename: Qing
authors.initials: Q
authors.lastname: Jiang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001786:Blood Glucose / Q000032:analysis*; D002384:Catalysis; D003035:Cobalt / Q000737:chemistry*; D003920:Diabetes Mellitus / Q000097:blood; D004553:Electric Conductivity; D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D008839:Microelectrodes; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry*; D016062:Porosity
chemical_list: D001786:Blood Glucose; D010087:Oxides; D003035:Cobalt; D006046:Gold; C060728:cobalt oxide