2000/05/31 by R. Scott Martin, Andrew J. Gawron, Susan M. Lunte +1 · 302 citations
Chemical Engineering · Chemistry · Engineering · #Analytical Chemistry (journal) #Analytical Chemistry and Sensors #Biosensors and Analytical Detection #Capillary action #Capillary electrophoresis #Catechol #Chemistry #Chromatography #Composite material #Electrochemistry #Electrode #Electropherogram #Layer (electronics) #Materials science #Microfluidic and Capillary Electrophoresis Applications #Nanotechnology #Reference electrode #Working electrode
paper · doi:10.1021/ac000160t
published in Analytical Chemistry 72(14), 3196-3202 (American Chemical Society)
openalex publication_date 2000/05/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
The development of a poly(dimethylsiloxane)-based (PDMS-based) microchip electrophoresis system employing dual-electrode electrochemical detection is described. This is the first report of dual-electrode electrochemical detection in a microchip format and of electrochemical detection on chips fabricated from PDMS. The device described in this paper consists of a top layer of PDMS containing the separation and injection channels and a bottom glass layer onto which gold detection electrodes have been deposited. The two layers form a tight reversible seal, eliminating the need for high-temperature bonding, which can be detrimental to electrode stability. The channels can also be temporarily removed for cleaning, significantly extending the lifetime of the chip. The performance of the chip was evaluated using catechol as a test compound. The response was linear from 10 to 500 microM with an LOD (S/N = 3) of 4 microM and a sensitivity of 45.9 pA/microM. Collection efficiencies for catechol ranged from 28.7 to 25.9% at field strengths between 200 and 400 V/cm. Dual-electrode detection in the series configuration was shown to be useful for the selective monitoring of species undergoing chemically reversible redox reactions and for peak identification in the electropherogram of an unresolved mixture.