title: Fabrication of a microfluidic Ag/AgCl reference electrode and its application for portable and disposable electrochemical microchips.
abstract: This report describes a convenient method for the fabrication of a miniaturized, reliable Ag/AgCl reference electrode with nanofluidic channels acting as a salt bridge that can be easily integrated into microfluidic chips. The Ag/AgCl reference electrode shows high stability with millivolt variations. We demonstrated the application of this reference electrode in a portable microfluidic chip that is connected to a USB-port microelectrochemical station and to a computer for data collection and analysis. The low fabrication cost of the chip with the potential for mass production makes it disposable and an excellent candidate for real-world analysis and measurement. We used the chip to quantitatively analyze the concentrations of heavy metal ions (Cd(2+) and Pb(2+)) in sea water. We believe that the Ag/AgCl reference microelectrode and the portable electrochemical system will be of interest to people in microfluidics, environmental science, clinical diagnostics, and food research.
authors.affiliation: Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P R China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Zhou
authors.forename: Kangning
authors.initials: K
authors.lastname: Ren
authors.forename: Yizhe
authors.initials: Y
authors.lastname: Zheng
authors.forename: Jing
authors.initials: J
authors.lastname: Su
authors.forename: Yihua
authors.initials: Y
authors.lastname: Zhao
authors.forename: Declan
authors.initials: D
authors.lastname: Ryan
authors.forename: Hongkai
authors.initials: H
authors.lastname: Wu
mesh_terms: D002104:Cadmium / Q000032:analysis; D004209:Disposable Equipment; D004566:Electrodes; D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D005456:Fluorescent Dyes / Q000737:chemistry; D007854:Lead / Q000032:analysis; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D049329:Nanostructures; D012623:Seawater / Q000737:chemistry; D012834:Silver / Q000737:chemistry*; D018030:Silver Compounds / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D018030:Silver Compounds; D002104:Cadmium; D007854:Lead; D012834:Silver; C037548:silver chloride