Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7558811 | Analytical Biochemistry | 2014 | 6 Pages |
Abstract
A sensitive electrochemical measurement system for hydroxyl radical (OH) was developed using enzyme-catalyzed signal amplification. In the presence of 2,6-xylenol as a trapping agent, glucose as a substrate, and pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) as a catalyst, the amperometric signal of the trapping adduct 2,6-dimethylhydroquinone (DMHQ) produced by the hydroxylation of 2,6-xylenol was able to be amplified and detected sensitively. The limit of detection (signal/noise [S/N]Â =Â 3) for DMHQ was 1Â nM. There was no significant interference from urate and other oxidizable compounds in the reaction mixture at the applied potential of 0Â V versus Ag/AgCl. This method was employed to observe the OH generation induced by the xanthine-xanthine oxidase (XO) system. The reaction rates of the DMHQ production induced from the xanthine-XO system in the presence and absence of various Fe(III) complexes and proteins were compared. Those with a free coordination site on the Fe atom effectively enhanced the OH generation.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Hirosuke Tatsumi, Yui Tsuchiya, Koichi Sakamoto,