title: Suitable combination of noble/ferromagnetic metal multilayers for enhanced magneto-plasmonic biosensing.
abstract: We present a theoretical and experimental study on the biosensing sensitivity of Au/Co/Au multilayers as transducers of the magneto-optic surface-plasmon-resonance (MOSPR) sensor. We demonstrate that the sensing response of these magneto-plasmonic (MP) transducers is a trade-off between the optical absorption and the magneto-optical activity, observing that the MP multilayer with larger MO effect does not provide the best sensing response. We show that it is possible to design highly-sensitive MP transducers able to largely surpass the limit of detection of the conventional surface-plasmon-resonance (SPR) sensor. This was proved comparing the biosensing performance of both sensors for the label-free detection of short DNA chains hybridization. For this purpose, we used and tested a novel label-free biofunctionalization protocol based on polyelectrolytes, which increases the resistance of MP transducers in aqueous environments.
authors.affiliation: Research Center on Nanoscience and Nanotechnology CIN2 (CSIC) and CIBER-BBN, Barcelona, Spain. david.regatos@cin2.es
authors.forename: David
authors.initials: D
authors.lastname: Regatos
authors.forename: Borja
authors.initials: B
authors.lastname: Sepúlveda
authors.forename: David
authors.initials: D
authors.lastname: Fariña
authors.forename: Laura G
authors.initials: LG
authors.lastname: Carrascosa
authors.forename: Laura M
authors.initials: LM
authors.lastname: Lechuga
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017403:In Situ Hybridization / Q000295:instrumentation*; D008280:Magnetics / Q000295:instrumentation*; D008670:Metals / Q000737:chemistry; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D018511:Systems Integration
chemical_list: D008670:Metals