Microfluidic Separation of Redox Reactions for Coulometry Based on Metallization at the Mixed Potential

Autor:	Shinnosuke Tsuchiya, Masatoshi Yokokawa, Fumihiro Sassa, Kazuhiro Ikemoto, Hiroaki Suzuki, Yui Nakaoka, Takafumi Seki, Shohei Kimura
Rok vydání:	2016
Předmět:	Detection limit Analyte 010401 analytical chemistry Analytical chemistry chemistry.chemical_element 010402 general chemistry Electrochemistry 01 natural sciences Redox 0104 chemical sciences Analytical Chemistry Coulometry Microelectrode chemistry Electrode Platinum
Zdroj:	Analytical Chemistry. 88:9427-9434
ISSN:	1520-6882 0003-2700
DOI:	10.1021/acs.analchem.6b01234
Popis:	Coulometric detection of an analyte in a solution at nanoliter scale was conducted by having redox reactions proceed simultaneously on a platinum electrode. The analyte was oxidized on a part of the electrode in one flow channel and silver was deposited on an array of circular microelectrodes formed in another flow channel at a mixed potential. Coulometric determination of the deposited silver showed a steep change in the generated charge as a result of the complete oxidation of silver. The short measurement time after the start of the coulometry suppressed the increase in background charge, resulting in significant lowering of the detection limit. The lower detection limit for H2O2 was 30 nM (3σ). To improve selectivity and minimize the influence of coexisting interferents, the shifting of the mixed potential, application of a permselective membrane, and electrochemical elimination of the interferents were effective modifications.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4ede6041b6fae81e31123047106273fe https://doi.org/10.1021/acs.analchem.6b01234 Zobrazit plný text záznamu