simple preparation of diaphorase electrode for detection of NAD+
- 발행기관 서강대학교 대학원
- 지도교수 신운섭
- 발행년도 2009
- 학위수여년월 2009. 8
- 학위명 석사
- 학과 일반대학원 바이오융합기술협동과정
- 실제URI http://www.dcollection.net/handler/sogang/000000045382
- 본문언어 영어
- 저작권 서강대학교의 논문은 저작권에 의해 보호받습니다
초록/요약
Abstract 1 The present work describes a method for the detection of NAD+ and NADH by simple preparation of the electrode by coimmobilization of diaphorase and polysiloxane viologen polymer electron mediator. The viologen polymer and diaphorase were entrapped on a glassy carbon electrode surface by drop-coated hydrophilic polyurethane. The modified electrode showed good electrocatalytic activities in NAD+ reduction and NADH oxidation. It showed a detection limit of 28 μM, a sensitivity of 0.22 nAμM-1, and a linear range from 0.2 mM to 4 mM for detecting NAD+. NADH sensing was also demonstrated. This sensing system of NAD+ was also coupled with glucose dehydrogenase to detect D-glucose. Abstract 2 Here we report a simple-prepared modified electrode for electrochemical detection of NAD+ and NADH. Propylamine viologen and diaphorase were crosslinked by poly (ethylene glycol (400) diglycidyl ether) onto printed electrode surface. By means of cyclic voltammetry and amperometry, the electrochemical characteristics of the modified electrode were described. As results shown, the modified electrode showed good electrochemical reactivity for detecting both NAD+ and NADH. Additionally, the modified electrode successfully detected NAD+ with a sensitivity of 14.8 nAμM-1 and a detection limit of 0.4 μM. The case of NADH detection showed a sensitivity of 24 nAμM-1 and a detection limit of 0.25 μM with a fast response time of 3 s (t90%). The pH profiles were also studied and for NAD+ reduction and NADH oxidation, respectively.
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