info:eu-repo/semantics/article
Dual monitoring of surface reactions in real time by combined surface-plasmon resonance and field-effect transistor interrogation
Fecha
2020-05-14Registro en:
Aspermair, Patrik; Ramach, Ulrich; Reiner Rozman, Ciril; Fossati, Stefan; Lechner, Bernadette; et al.; Dual monitoring of surface reactions in real time by combined surface-plasmon resonance and field-effect transistor interrogation; American Chemical Society; Journal of the American Chemical Society; 142; 27; 14-5-2020; 11709-11716
0002-7863
1520-5126
CONICET Digital
CONICET
Autor
Aspermair, Patrik
Ramach, Ulrich
Reiner Rozman, Ciril
Fossati, Stefan
Lechner, Bernadette
Moya, Sergio Enrique
Azzaroni, Omar
Dostalek, Jakub
Szunerits, Sabine
Knoll, Wolfgang
Bintinger, Johannes
Resumen
By combining surface plasmon resonance (SPR) and electrolyte gated field-effect transistor (EG-FET) methods in a single analytical device we introduce a novel tool for surface investigations, enabling simultaneous measurements of the surface mass and charge density changes in real time. This is realized using a gold sensor surface that simultaneously serves as a gate electrode of the EG-FET and as the SPR active interface. This novel platform has the potential to provide new insights into (bio)adsorption processes on planar solid surfaces by directly relating complementary measurement principles based on (i) detuning of SPR as a result of the modification of the interfacial refractive index profile by surface adsorption processes and (ii) change of output current as a result of the emanating effective gate voltage modulations. Furthermore, combination of the two complementary sensing concepts allows for the comparison and respective validation of both analytical techniques. A theoretical model is derived describing the mass uptake and evolution of surface charge density during polyelectrolyte multilayer formation. We demonstrate the potential of this combined platform through the observation of layer-bylayer assembly of PDADMAC and PSS. These simultaneous label-free and real-time measurements allow new insights into complex processes at the solid−liquid interface (like non-Fickian ion diffusion), which are beyond the scope of each individual tool.