Electrochemical reactions of highly active nitroxyl radicals with thiol compounds

Masayuki Kumano; Kyoko Sugiyama; Fumiya Sato; Sachiko Komatsu; Kazuhiro Watanabe; Tetsuya Ono; Kentaro Yoshida; Yusuke Sasano; Yoshiharu Iwabuchi; Tsutomu Fujimura; Yoshitomo Kashiwagi; Katsuhiko Sato

doi:10.1007/s44211-022-00246-9

Electrochemical reactions of highly active nitroxyl radicals with thiol compounds

Anal Sci. 2023 Mar;39(3):369-374. doi: 10.1007/s44211-022-00246-9. Epub 2022 Dec 28.

Affiliations

¹ Faculty of Pharmaceutical Science, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba, Sendai, Miyagi, 981-8558, Japan.
² School of Pharmaceutical Sciences, Ohu University, 31-1 Misumido, Tomita-Machi, Koriyama, Fukushima, 963-8611, Japan.
³ Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan.
⁴ School of Pharmaceutical Sciences, Ohu University, 31-1 Misumido, Tomita-Machi, Koriyama, Fukushima, 963-8611, Japan. y-kashiwagi@pha.ohu-u.ac.jp.
⁵ Faculty of Pharmaceutical Science, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba, Sendai, Miyagi, 981-8558, Japan. satok@tohoku-mpu.ac.jp.

PMID: 36576651
DOI: 10.1007/s44211-022-00246-9

Abstract

Nitroxyl radicals are known to electrochemically oxidize thiols as well as alcohols and amines. In this study, a preliminary investigation of the electrochemical reaction of thiols with 9-azabicyclo[3.3.1]nonane N-oxyl (ABNO), 2-azaadamantane N-oxyl (AZADO), and nortropine N-oxyl (NNO), which are highly active due to their bicyclo structures, for use in electrochemical analysis was performed and the results were compared with those for a typical nitroxyl radical compound, 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO). Mercaptopropane sulfonic acid (MPS) was used as a model compound to investigate the electrochemical response in aqueous solution. In addition, electrochemical detection of glutathione, a biological thiol molecule, was performed.

Keywords: Electrochemical analysis; Electrochemical reaction; Nitroxyl radical; Thiol compounds.