Analytical Sciences

Abstract − Analytical Sciences, 29(1), 79 (2013).

Fabrication and Characterization of a Thermostable Quinoprotein Aldose Sugar Dehydrogenase Immobilized Electrode
Yohei YAMADA,* Tetsuya HAYASHI,* Haruhiko SAKURABA,** Tomoki YABUTANI,* and Toshio TAKAYANAGI*
*Department of Chemical Science and Technology, Institute of Science and Technology, The University of Tokushima, 2-1 Minami-josanjima, Tokushima 770-8506, Japan
**Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kita, Kagawa 761-0795, Japan
We fabricated a thermostable quinoprotein aldose sugar dehydrogenase (tPQQ-ASD derived from a hyperthermophilic archaeon Pyrobaculum aerophilum) immobilized electrode. The electrode was prepared by immobilizing agarose gel mixed with the enzyme and carbon nanofiber (CNF) on a carbon paste (CP) electrode containing p-benzoquinone (BQ) as an electron mediator. The electrocatalytic response was clearly observed by the addition of D-glucose at the electrode. The electrode properties such as pH, temperature dependency and substrate selectivity basically followed the enzyme properties. The current response against D-glucose increased with measurement temperatures up to 70°C, and response perturbation caused by dissolved oxygen level was not observed at the electrode. As for the results of long-term stability evaluation, the current response was stable for 30 days when the electrode was stored in HEPES buffer solution (pH 7.0) at 4°C.