title: Hybridization chain reaction performed on a metal surface as a means of signal amplification in SPR and electrochemical biosensors.
abstract: A more specific and intense signal is desirable for most kinds of biosensors for biomedical or environmental applications, and it is especially so for label-free biosensors. In this paper, we show that hybridization chain reaction (HCR) can be exploited for the easily detectable accumulation of nucleic acids on metal surfaces as an event triggered by specific recognition between a probe and a target nucleic acid. We show that this process could be exploited to increase the sensitivity in the detection of nucleic acids derived from a pathogenic microorganism. This strategy can be straightforwardly implemented on SPR biosensors (commercial or custom-built) or on label-free electrochemical biosensors. Together with signal amplification, HCR can serve as a confirmation of the specificity of target recognition, as it involves the specific matching with a separate base sequence in the target nucleic acid. Furthermore, the kinetics of the target binding and the HCR can be easily distinguished from each other, providing an additional means of confirmation of the specific recognition.
authors.affiliation: Institute of Bioengineering at the Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
authors.forename: Fabio M
authors.initials: FM
authors.lastname: Spiga
authors.affiliation: Department of Electronics Technology at the Budapest University of Technology and Economics, Budapest, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Bonyár
authors.affiliation: Department of Electronics Technology at the Budapest University of Technology and Economics, Budapest, Hungary.
authors.forename: Balázs
authors.initials: B
authors.lastname: Ring
authors.affiliation: Interdepartmental Center for Industrial Research on Health Sciences & Technologies, University of Bologna, Via Irnerio 48, Bologna 40126, Italy.
authors.forename: Manuele
authors.initials: M
authors.lastname: Onofri
authors.affiliation: Department of Pharmacy and Biotechnologies at the University of Bologna, Via Irnerio 48, Bologna 40126, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Vinelli
authors.affiliation: Department of Electronics Technology at the Budapest University of Technology and Economics, Budapest, Hungary.
authors.forename: Hunor
authors.initials: H
authors.lastname: Sántha
authors.affiliation: Institute of Bioengineering at the Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
authors.forename: Carlotta
authors.initials: C
authors.lastname: Guiducci
authors.affiliation: Interdepartmental Center for Industrial Research on Health Sciences & Technologies, University of Bologna, Via Irnerio 48, Bologna 40126, Italy; Department of Pharmacy and Biotechnologies at the University of Bologna, Via Irnerio 48, Bologna 40126, Italy; Istituto Nanoscienze of the National Research Council, S3 Laboratory, Italy. Electronic address: giampaolo.zuccheri@unibo.it.
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Zuccheri
mesh_terms: D004247:DNA / Q000032:analysis*; D055664:Electrochemical Techniques / Q000295:instrumentation*; D004867:Equipment Design; D057230:Limit of Detection; D008670:Metals / Q000737:chemistry; D009693:Nucleic Acid Hybridization; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D013499:Surface Properties
chemical_list: D008670:Metals; D004247:DNA
keywords: DNA biosensors; Electrochemical biosensors; Hybridization chain reaction; Label-free biosensors; Surface plasmon resonance