Ferrocene‐containing polymers as electron transfer mediators in carbon paste electrodes modified with PQQ‐dependent aldose dehydrogenase

Abstract

The aim of this work was to improve an aldose-detecting biosensor based on quinoprotein aldose dehydrogenase (ALDH). Polymer-bound ferrocene derivatives with four different structures were studied as electron transfer mediators between the coenzyme of ALDH, pyrroloquinoline qninone (PQQ), and the conducting electrode material. The ferrocene polymers were mixed into carbon paste, which was used for the preparation of aldose-detecting electrodes by immobilizing ALDH on the carbon paste surface by adsorption. The current responses of the ferrocene polymer modified electrodes were studied and the effect of the polymer structure on the response was examined.The electrodes modified with all four polymers showed maximum response at the working potential around 300 mV (vs. Ag/AgCl). The operational stability of the ferrocene polymer modified electrodes was better than that of corresponding dimethylferrocene modified electrodes. The ferrocene polymer modified electrodes seemed to be suitable for the measurement of real samples.

Amperometric Biosensors for Detection of Sugars Based on the Electrical Wiring of Different Pyranose Oxidases and Pyranose Dehydrogenases with Osmium Redox Polymer on Graphite Electrodes

“…There are a number of other sugar oxidizing enzymes with bound cofactors. Some of them have been previously used for biosensor constructions, e.g., hexose oxidase [7], oligosaccharide dehydrogenase [8 -10], aldose dehydrogenase [11], cellobiose dehydrogenase [12,13], carbohydrate oxidase [14] and pyranose oxidase [15,16]. In the present work, electrical wiring of various forms of two different sugar oxidizing enzymes, i.e., pyranose oxidase (P2O), both wild type and a mutant, as well as one commercial P2O, and additionally pyranose dehydrogenase (PDH) from two different origins, with an osmium redox polymer, (poly(1-vinylimidazole) 12 -[Os(4,4'-dimethyl-2,2'-dipyridyl) 2 Cl 2 ] 2þ/þ ), is reported.…”

Fabrication and Characterization of a Thermostable Quinoprotein Aldose Sugar Dehydrogenase Immobilized Electrode

“…In fact, Smolander et al reported a PQQ-aldose dehydrogenase modified carbon paste (CP) electrode for flow-injection analysis of aldose sugars. 25,26 They succeeded to improve the sensor stability by preventing leaking of the enzyme with a polymer external membrane. However, long-term stability was certified only for one day, and it was insufficient for practical use.…”

Characterization and Stability Study of Immobilized PQQ‐Dependent Aldose Dehydrogenase Bioanodes

“…In addition the presence of oxygen does not affect the catalytic activity of the enzyme, which is a problem in the case of glucose oxidase. ALDH enzyme was previously shown to work in amperometric sensors for xylose and glucose [3,4,11]. Due to the two electron oxidation reaction of glucose:…”