title: Development of stable and reproducible biosensors based on electrochemical impedance spectroscopy: three-electrode versus two-electrode setup.
abstract: This work focuses on the development of electrochemical impedance biosensors based on capacitance readout, for the detection of biomolecules in small sample volumes. We performed electrochemical impedance spectroscopy (EIS) measurements of DNA hybridization in electrochemical cells with microfabricated gold electrodes. The time stability of the device was tested in two different configurations: two microelectrodes in a microfluidic channel; two microelectrodes plus a reference electrode in an electrochemical cell. Our results demonstrate that the three-electrode setup is more stable, more reproducible, and suitable for real-time measurements. In the last part of the work we perform a test study of DNA hybridization in real time, and we show that the three-electrode configuration can measure the process in situ and in real time.
authors.affiliation: SISSA, via Bonomea, 265, 34136 Trieste, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Ianeselli
authors.affiliation: CNR-IOM, Laboratorio TASC, Area Science Park, Basovizza, Strada Statale 14 km 163.5, Trieste I-34149, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Grenci
authors.affiliation: Elettra-Sincrotrone Trieste S.C.p.A., S.S. 14 km 163.5, In Area Science Park, Basovizza, Trieste 34149, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Callegari
authors.affiliation: CNR-IOM, Laboratorio TASC, Area Science Park, Basovizza, Strada Statale 14 km 163.5, Trieste I-34149, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Tormen
authors.affiliation: Elettra-Sincrotrone Trieste S.C.p.A., S.S. 14 km 163.5, In Area Science Park, Basovizza, Trieste 34149, Italy. Electronic address: loredana.casalis@elettra.eu.
authors.forename: Loredana
authors.initials: L
authors.lastname: Casalis
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004247:DNA / Q000032:analysis / Q000737:chemistry* / Q000235:genetics*; D058266:Dielectric Spectroscopy / Q000295:instrumentation*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017403:In Situ Hybridization / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004247:DNA
keywords: DNA hybridization; DNA self-assembling; EIS; Real-time biosensors