title: Enzymatically enhanced collisions on ultramicroelectrodes for specific and rapid detection of individual viruses.
abstract: We report the specific collision of a single murine cytomegalovirus (MCMV) on a platinum ultramicroelectrode (UME, radius of 1 μm). Antibody directed against the viral surface protein glycoprotein B functionalized with glucose oxidase (GOx) allowed for specific detection of the virus in solution and a biological sample (urine). The oxidation of ferrocene methanol to ferrocenium methanol was carried out at the electrode surface, and the ferrocenium methanol acted as the cosubstrate to GOx to catalyze the oxidation of glucose to gluconolactone. In the presence of glucose, the incident collision of a GOx-covered virus onto the UME while ferrocene methanol was being oxidized produced stepwise increases in current as observed by amperometry. These current increases were observed due to the feedback loop of ferrocene methanol to the surface of the electrode after GOx reduces ferrocenium methanol back to ferrocene. Negative controls (i) without glucose, (ii) with an irrelevant virus (murine gammaherpesvirus 68), and (iii) without either virus do not display these current increases. Stepwise current decreases were observed for the prior two negative controls and no discrete events were observed for the latter. We further apply this method to the detection of MCMV in urine of infected mice. The method provides for a selective, rapid, and sensitive detection technique based on electrochemical collisions.
authors.affiliation: Center for Electrochemistry, Department of Chemistry, The University of Texas at Austin, Austin, TX 78712;
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Dick
authors.affiliation: Department of Molecular Biosciences, LaMontagne Center for Infectious Disease, and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712.
authors.forename: Adam T
authors.initials: AT
authors.lastname: Hilterbrand
authors.affiliation: Center for Electrochemistry, Department of Chemistry, The University of Texas at Austin, Austin, TX 78712;
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Strawsine
authors.affiliation: Department of Molecular Biosciences, LaMontagne Center for Infectious Disease, and Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712.
authors.forename: Jason W
authors.initials: JW
authors.lastname: Upton
authors.affiliation: Center for Electrochemistry, Department of Chemistry, The University of Texas at Austin, Austin, TX 78712; ajbard@cm.utexas.edu.
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Bard
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000737:chemistry / Q000276:immunology; D000956:Antigens, Viral / Q000737:chemistry / Q000276:immunology; D003587:Cytomegalovirus; D055664:Electrochemical Techniques; D005296:Ferrous Compounds / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry*; D005949:Glucose Oxidase / Q000737:chemistry*; D008810:Mice, Inbred C57BL; D008839:Microelectrodes; D010984:Platinum / Q000737:chemistry; D014556:Urine / Q000821:virology*; D014759:Viral Envelope Proteins / Q000276:immunology; D014771:Virion
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D005296:Ferrous Compounds; D014759:Viral Envelope Proteins; C040495:glycoprotein B, Simplexvirus; C071550:ferrocenemethanol; D010984:Platinum; D005949:Glucose Oxidase; D005947:Glucose
keywords: ELISA; collisions; cytomegalovirus; electrochemistry; electrovirology