Open AccessContinuous and selective measurement of oxytocin and vasopressin using boron-doped diamond electrodes
Author(s) -
Kai Asai,
Tribidasari A. Ivandini,
Yasuaki Einaga
Publication year - 2016
Publication title -
scientific reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.24
H-Index - 213
ISSN - 2045-2322
DOI - 10.1038/srep32429
Subject(s) - electrode , chronoamperometry , cyclic voltammetry , microelectrode , oxytocin , detection limit , diamond , electrochemistry , vasopressin , materials science , analytical chemistry (journal) , inorganic chemistry , chemistry , chromatography , medicine , composite material
The electrochemical detection of oxytocin using boron-doped diamond (BDD) electrodes was studied. Cyclic voltammetry of oxytocin in a phosphate buffer solution exhibits an oxidation peak at +0.7 V ( vs . Ag/AgCl), which is attributable to oxidation of the phenolic group in the tyrosyl moiety. Furthermore, the linearity of the current peaks obtained in flow injection analysis (FIA) using BDD microelectrodes over the oxytocin concentration range from 0.1 to 10.0 μM with a detection limit of 50 nM ( S / N = 3) was high ( R 2 = 0.995). Although the voltammograms of oxytocin and vasopressin observed with an as-deposited BDD electrode, as well as with a cathodically-reduced BDD electrode, were similar, a clear distinction was observed with anodically-oxidized BDD electrodes due to the attractive interaction between vasopressin and the oxidized BDD surface. By means of this distinction, selective measurements using chronoamperometry combined with flow injection analysis at an optimized potential were demonstrated, indicating the possibility of making selective in situ or in vivo measurements of oxytocin.