Optical and electronic signal stabilization of plasmonic fiber optic gate electrodes: towards improved real-time dual-mode biosensing

0574621 - FZÚ 2024 RIV CH eng J - Journal Article
Hasler, R. - Steger-Polt, M.H. - Reiner-Rozman, C. - Fossati, S. - Lee, S. - Aspermair, P. - Kleber, C. - Ibanez, M. - Dostálek, Jakub - Knoll, W.
Optical and electronic signal stabilization of plasmonic fiber optic gate electrodes: towards improved real-time dual-mode biosensing.
Frontiers in Physics. Roč. 11, July (2023), č. článku 1202132. ISSN 2296-424X. E-ISSN 2296-424X
Institutional support: RVO:68378271
Keywords : fiber optic * surface plasmon resonance * field-effect transistor * annealing * signal stabilization * real-time sensing
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 3.1, year: 2022
Method of publishing: Open access

The use of multimodal readout mechanisms next to label-free real-time monitoring of biomolecular interactions can provide valuable insight into surface-based reaction mechanisms. To this end, the combination of an electrolyte-gated field-effect transistor (EG-FET) with a fiber optic-coupled surface plasmon resonance (FO-SPR) probe serving as gate electrode has been investigated to deconvolute surface mass and charge density variations associated to surface reactions. However, applying an electrochemical potential on such gold-coated FO-SPR gate electrodes can induce gradual morphological changes of the thin gold film, leading to an irreversible blue-shift of the SPR wavelength and a substantial signal drift. We show that mild annealing leads to optical and electronic signal stabilization (20-fold lower signal drift than as-sputtered fiber optic gates) and improved overall analytical performance characteristics.
Permanent Link: https://hdl.handle.net/11104/0346097