Amperometric glucose biosensors based on Prussian Blue– and polyaniline–glucose oxidase modified electrodes

Inkjet Printed Prussian Blue Films for Hydrogen Peroxide Detection

“…[1][2][3] To transform chemical information into electric signals, one needs the assembly of many biosensors that involves amperometric configuration with oxidase enzymes. [2][3][4][5][6][7] These enzymes oxidize specific substrates and then return into their original state by transferring electrons to molecular oxygen. Thus, in many oxidase-based sensors, hydrogen peroxide (H2O2) is produced as a side product, and the production rate of H2O2 can provide information about initial concentrations of the enzyme substrates.…”

“…Thus, in many oxidase-based sensors, hydrogen peroxide (H2O2) is produced as a side product, and the production rate of H2O2 can provide information about initial concentrations of the enzyme substrates. [2][3][4][6][7][8][9][10] Direct electrochemical detection for H2O2 oxidation, however, needs an electric potential of around 0.7 V versus Ag/AgCl, at which many other substances in real samples, such as uric acid and ascorbic acid, could also be oxidized. Such a process results in large interfering signals.…”

“…3,6,10 To reduce the large overpotential, Prussian blue (ferric hexacyanoferrate, or PB) has been found to be a great mediating agent for H2O2 detection in bio-oxidation, because of its great catalytic activity at low electric voltage toward H2O2. 3,4,6,7,11,12 The decrease in applied voltages, with avoidance of interfering signals, provides a more specific and accurate detection; thus, PB-modified electrodes have been recently adopted in many amperometric measurements for H2O2. 4,13 Regular configuration of amperometric measurements for H2O2 consists of a conductive lead connected to a surfacemodified electrode, on which a PB layer is deposited.…”

“…4,13 Regular configuration of amperometric measurements for H2O2 consists of a conductive lead connected to a surfacemodified electrode, on which a PB layer is deposited. Various methods, such as spontaneous chemical reactions, 11,12,14,15 potential cycling method 4,7 and galvanostatic method, 8,9,[16][17][18][19][20][21] have been proposed to modify electrode surfaces. The detection limit of the PB-modified electrodes can be as low as 10 -8 M with a wide linear range of up to 10 -2 M. 13 Although electrode surfaces after electrochemical treatment can be fairly sensitive, these processes can be time consuming and usually operate batchwise.…”

Enhancement of Bioelectrocatalytic Oxidation of Glucose by Application of Tetrathiafulvalene Modified Carbon Nanotubes as Mediating System

“…Further, as a biofuel, glucose is widely available in the environment. GOx has been immobilized on various kinds of matrices and carriers, for example, entrapping into sol-gel matrix (16,17), incorporating into polymer films (18)(19)(20), covalently linking to the electrode surface, or immobilizing onto self-assembled monolayers (21,22) and onto the surface of carbon nanotubes (23)(24)(25). Although there are many investigations of GOx, only a few examples of quasi-reversible voltammograms for direct electron transfer between the GOx active site and the electrode surface are reported (22,23).…”