Analytical Sciences

Abstract − Analytical Sciences, 23(1), 55 (2007).

Construction of a Dimethyl Sulfoxide Sensor Based on Dimethyl Sulfoxide Reductase Immobilized on a Au Film Electrode
Hiroki YONEHARA,* Shin-ichiro FUJII,** Kiichi SATO,* Mitsuru ABO,* and Etsuro YOSHIMURA*
*Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi 1-1-1, Bunkyo, Tokyo 113-8657, Japan
**Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan
A novel dimethyl sulfoxide (DMSO) sensor using DMSO reductase and film electrodes was constructed. The Au and Ag electrodes were fabricated on slide glass by vacuum deposition and the application of a photolithographic technique. The micro-chamber (4 × 50 × 1 mm, volume 200 µl) was fabricated on a poly(dimethylsiloxane) (PDMS) polymer. The Pt electrode was implanted in a PDMS polymer. DMSO reductase was immobilized on a Au film electrode with bovine serum albumin (BSA)-glutaraldehyde. This sensor could determine DMSO in an unpurged aqueous solution with glucose oxidase (GOD) and catalase (CAT) for oxygen removal. The DMSO sensor showed a linear response within 1 mM DMSO with a correlation coefficient of 0.999. The detection limit was 200 µM (3σ), and the sensitivity was 23.8 mA M-1 cm-2. The relative standard deviations at each concentration were within 3.6%.