title: Determination of nickel(II) by ion-transfer to hydroxide medium using sequential injection-electrochemical analysis (SIECA).
abstract: A method for the determination of Ni(II) using ion-transfer to a hydroxide medium has been developed by the sequential injection-electrochemical analysis (SIECA), a combination between an automated flow-based analysis and electrochemical techniques with a homemade screen-printed carbon electrode (SPCE). A sample/standard solution was introduced into an electrochemical flow cell where the Ni(II) in the solution was electrochemically reduced and accumulated on the SPCE. The accumulated Ni was then oxidized to Ni(II) in a hydroxide medium, which led to the formation of nickel hydroxide (Ni(OH)2) and nickel oxyhydroxide (NiOOH) on the SPCE. The electrochemical response associated with Ni(OH)2and NiOOH was subsequently determined by square-wave voltammetry to account for Ni(II). Under optimal conditions, the proposed method provides a low detection limit of 0.02mgmL-1. This method was further applied to determine the Ni(II) content of standard-spiked mineral water samples with satisfactory results.
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Eakkasit
authors.initials: E
authors.lastname: Punrat
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Panunporn
authors.initials: P
authors.lastname: Tutiyasarn
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Suchada
authors.initials: S
authors.lastname: Chuanuwatanakul
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand. Electronic address: corawan@chula.ac.th.
authors.forename: Orawon
authors.initials: O
authors.lastname: Chailapakul
keywords: Nickel detection; Screen-printed carbon electrode; Sequential injection analysis; Square-wave voltammetry; Stripping voltammetry