Voltammetric and spectroscopic studies of pyrroloquinoline quinone coenzyme under neutral and basic conditions |
| |
| Institution: | 1. Institute for Medical Research and Occupational Health, Ksaverska cesta 2, HR-10000 Zagreb, Croatia;2. “Ru?er Bo?kovi?” Institute, Bijeni?ka 54, HR-10000 Zagreb, Croatia;1. Physics Department, Faculty of Sciences, Hashemite University, Zarqa, Jordan;2. Medical Imaging Department, Faculty of Allied Health Sciences, Hashemite University, Zarqa, Jordan;1. Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan;2. School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK |
| |
| Abstract: | The voltammetric and spectroscopic properties of pyrroloquinoline quinone (PQQ) have been investigated in the pH range from 5 to 13.5. PQQ gives a reversible cyclic voltammogram at the mercury electrode, which is ascribed to a two-step one-electron redox reaction of the o-quinone moiety. Digital simulation analysis of the reversible voltammogram made it possible to evaluate the standard redox potentials of the PQQ/pyrroloquinoline semiquinone (PQQsem) and PQQsem/pyyroloquinoline quinol (PQQred) couples. From the redox potential vs. pH relationships, the acid dissociation constants of PQQ, PQQsem, and PQQred have also been determined. The absorption and electron spin resonance spectroscopic properties are explained by the acid-base and redox equilibria proposed here. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
