title: Application of capacitively coupled contactless conductivity as an external detector for zone electrophoresis in poly(dimethylsiloxane) chips.
abstract: In this work, lab-made PDMS microfluidic chips were matched to a capacitively coupled contactless conductivity detector (C(4) D) having external in-plane electrodes (eDAQ, Australia). The advantages of this type of C(4) D are the choice to reversibly place or remove the microchip onto/from the detector and to freely variate the position of the detection (separation length) on the microchip. The thickness of the bottom layer of the PDMS chip was optimized to achieve sensitive detection during the electrophoretic separation. PDMS chips with 100 μm bottom layer used with the C(4) D platform were tested by CZE of a mixture of seven anions and different types of real samples. Using split-flow pressure sample injection and effective length of 6.5 cm, the numbers of theoretical plates were in the range of 4000-6000 (63,000-93,000/m) and the LODs amounted to 3.66-14.7 μmol/L (0.13-2.26 μg/mL) for the studied anions.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary.
authors.forename: Péter I
authors.initials: PI
authors.lastname: Koczka
authors.affiliation: Department of Analytical Chemistry, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj Napoca, Romania.
authors.forename: Ede
authors.initials: E
authors.lastname: Bodoki
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Gáspár
mesh_terms: D000838:Anions / Q000032:analysis; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D060766:Drinking Water / Q000737:chemistry; D004553:Electric Conductivity; D046209:Electrophoresis, Microchip / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D006801:Humans; D057230:Limit of Detection; D012463:Saliva / Q000737:chemistry; D014100:Toothpastes / Q000737:chemistry
chemical_list: D000838:Anions; D004129:Dimethylpolysiloxanes; D060766:Drinking Water; D014100:Toothpastes; C013830:baysilon
keywords: Capacitively coupled contactless conductivity; Microchip electrophoresis; Poly(dimethylsiloxane)