Integrated oligoaniline-cross-linked composites of Au nanoparticles/glucose oxidase electrodes: a generic paradigm for electrically contacted enzyme systems.
Sweet sensor: A bis-aniline-cross-linked Au nanoparticles (NPs)/glucose oxidase composite has been electropolymerized on a Au electrode (see picture). The integrated Au NPs/enzyme electrode provides an effective matrix for making electrical contact with the enzyme, and this yields a specific amperometric glucose biosensor.Electropolymerizable glucose oxidase (GOx) was synthesized by the tethering of thioaniline units to the protein. The electropolymerization of the thioaniline-modified GOx in the presence of thioaniline-functionalized Au nanoparticles (NPs) yielded a three-dimensional bis-aniline-cross-linked Au NPs/GOx network. The bis-aniline bridging units are redox active and mediate the electron transfer between the enzyme redox sites and the electrode, and the Au NPs provide the three-dimensional conductivity for transporting the electrons to the electrode. The covalently linked GOx displays an effective electrical contact with the electrode (turnover rate of ca. 500 s(-1)), which results in a sensitive and selective glucose-sensing electrode. The preparation of the electrode by means of electropolymerization, and the bioelectrocatalytic features of the electrode, suggest its feasibility as a miniaturized electrode with a sensing matrix and as an implantable glucose sensor in future applications.
Yehezkeli
Omer
O
Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, Israel.
Yan
Yi-Ming
YM
Baravik
Ilina
I
Tel-Vered
Ran
R
Willner
Itamar
I
D000814:Aniline Compounds / Q000737:chemistry*; D015374:Biosensing Techniques; D004563:Electrochemistry; D004566:Electrodes; D005949:Glucose Oxidase / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053758:Nanoparticles
D000814:Aniline Compounds; D006046:Gold; D005949:Glucose Oxidase