アブストラクト（31巻1号：The Bulletin of Kanagawa Dental College）

The Bulletin of Kanagawa Dental College

English

Title　： Design of Optical Biosensor : an Application to Detect Oxygen-derived Radical Generating Pathway in Ischemia-reperfusion
Subtitle　： ORIGINAL ARTICLES
Authors　： Kazuo Todoki1,2, Yoichi Omori1, Shigeru Shimada1, Masaich-Chang-il Lee1, Shun-suke Takahashi1
Authors（kana）　：
Organization　： 1Department of Pharmacology and ESR Laboratories, Kanagawa Dental College, 2Institute for Frontier Oral Science, Kanagawa Dental College
Journal　： The Bulletin of Kanagawa Dental College
Volume　： 31
Number　： 1
Page　： 33-37
Year/Month　： 2003 / 3
Article　： Original article
Publisher　： Kanagawa Odontological Society
Abstract　： The aims of this study are to design and develop an optical biosensor that can be used without renewing reagents in the probe for detecting biologically important analytes and to apply the developed optical biosensor to measure the purine metabolism in an ischemia-reperfusion model. We developed the chemiluminometric bienzyme sensors on the basis of the horseradish peroxidase catalyzed hydrogen peroxide (H2O2) / luminol reaction; horse-radish peroxidase was coimmobilized with xanthine oxidase. An optical biosensor probe with a photo multiplier tube (PMP) and an integrated preamplifier was investigated to detect chemiluminescence. The specificity for hypoxanthine was obtained by immobilizing the enzyme xanthine oxidase in a layer of sodium alginate gel over the PMP. The superoxide anion radical (O2・-) was produced in the presence of xanthine oxidase and hypoxanthine by application of the enzyme catalyzed reaction of hypoxanthine and oxygen. Immediately, the H2O2 generated from the dismutation reaction of O2・- was detected by the luminol chemiluminescence that is enhanced by horseradish peroxidase. The linear relation between chemiluminescence intensity and hypoxanthine concentration ranging from 10-6 M/L to 10-9 M/L was obtained. The concentration of hypoxanthine in rabbit plasma was also determined in peripheral blood samples (obtained from auricular vein). Hypoxanthine increased from 0.68+-0.1 μM/L to 4.5+-3.9 μM/L (mean+-S.D., n=3. P<0.05) was demonstrated in plasma obtained immediately after 90 mins of auricular artery occlusion. Using this optical biosensor, it was possible to evaluate the role of endogenous substances responsible for the generation of oxygen-derived free radicals.
Practice　： Dentistry
Keywords　： Optical biosensor, Ischemia-reperfusion, Hypoxanthine, Luminol