title: Electrochemical synthesis of reduced graphene sheet-AuPd alloy nanoparticle composites for enzymatic biosensing.
abstract: A simple, fast, green and controllable approach was developed for electrochemical synthesis of a novel nanocomposite of electrochemically reduced graphene oxide (ERGO) and gold-palladium (1:1) bimetallic nanoparticles (AuPdNPs), without the aid of any reducing reagent. The electrochemical reduction efficiently removed oxygen-containing groups in ERGO, which was then modified with homogeneously dispersed AuPdNPs in a good size distribution. ERGO-AuPdNPs nanocomposite showed excellent biocompatibility, enhanced electron transfer kinetics and large electroactive surface area, and were highly sensitive and stable towards oxygen reduction. A biosensor was constructed by immobilizing glucose oxidase as a model enzyme on the nanocomposites for glucose detection through oxygen consumption during the enzymatic reaction. The biosensor had a detection limit of 6.9μM, a linear range up to 3.5mM and a sensitivity of 266.6μAmM(-1)cm(-2). It exhibited acceptable reproducibility and good accuracy with negligible interferences from common oxidizable interfering species. These characteristics make ERGO-AuPdNPs nanocomposite highly suitable for oxidase-based biosensing.
authors: Food & Bioproces Engineering Laboratory Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, WI 53706, USA.
authors: Jiang
authors: J
authors: Yang
authors: Shengyuan
authors: S
authors: Deng
authors: Jianping
authors: J
authors: Lei
authors: Huangxian
authors: H
authors: Ju
authors: Sundaram
authors: S
authors: Gunasekaran
mesh_terms: D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D001786:Blood Glucose / Q000032:analysis; D055664:Electrochemical Techniques; D004800:Enzymes, Immobilized; D005949:Glucose Oxidase; D006047:Gold Alloys; D006108:Graphite; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry / Q000648:ultrastructure; D010084:Oxidation-Reduction; D010165:Palladium; D013499:Surface Properties
chemical_list: D001786:Blood Glucose; D004800:Enzymes, Immobilized; D006047:Gold Alloys; D010165:Palladium; D006108:Graphite; D005949:Glucose Oxidase