title: Peptide nanotube-modified electrodes for enzyme-biosensor applications.
abstract: The fabrication and notably improved performance of composite electrodes based on modified self-assembled diphenylalanine peptide nanotubes is described. Peptide nanotubes were attached to gold electrodes, and we studied the resulting electrochemical behavior using cyclic voltammetry and chronoamperometry. The peptide nanotube-based electrodes demonstrated a direct and unmediated response to hydrogen peroxide and NADH at a potential of +0.4 V (vs SCE). This biosensor enables a sensitive determination of glucose by monitoring the hydrogen peroxide produced by an enzymatic reaction between the glucose oxidase attached to the peptide nanotubes and glucose. In addition, the marked electrocatalytic activity toward NADH enabled a sensitive detection of ethanol using ethanol dehydrogenase and NAD+. The peptide nanotube-based amperometric biosensor provides a potential new tool for sensitive biosensors and biomolecular diagnostics.
authors.affiliation: Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Miri
authors.initials: M
authors.lastname: Yemini
authors.forename: Meital
authors.initials: M
authors.lastname: Reches
authors.forename: Ehud
authors.initials: E
authors.lastname: Gazit
authors.forename: Judith
authors.initials: J
authors.lastname: Rishpon
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D004566:Electrodes; D005947:Glucose / Q000032:analysis / Q000378:metabolism; D005949:Glucose Oxidase / Q000378:metabolism*; D006046:Gold; D006861:Hydrogen Peroxide / Q000378:metabolism; D008855:Microscopy, Electron, Scanning; D009249:NADP / Q000378:metabolism; D045333:Nanotubes, Peptide / Q000737:chemistry* / Q000648:ultrastructure; D012680:Sensitivity and Specificity
chemical_list: D045333:Nanotubes, Peptide; D009249:NADP; D006046:Gold; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D005947:Glucose