We summarize some features of the recently introduced surface–plasmon field‐enhanced fluorescence spectroscopy (SPFS): a novel technique offering an increased sensitivity for monitoring interfacial binding reactions in biosensor formats. We briefly discuss the enhancement factors obtainable at resonant excitation of surface–plasmon modes propagating along a (noble) metal/dielectric interface and refer to the (Förster) energy transfer mechanisms operating for chromophores excited near metal surfaces. As a first example, we present data obtained during the binding of fluorophore‐doped latex particles to a functionalized interface. Then, experiments are described with surface‐attached oligonucleotide catcher probes and complementary target strands from solution, demonstrating the potential of SPFS for monitoring hybridization reactions.

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We have used a combination of surface plasmon resonance (SPR) and the quartz crystal microbalance (QCM) to monitor in situ the solution-phase adsorption of the perfluoropolyether lubricant Fomblin ZDOL onto a silver surface. This dual-probe technique was then extended in a novel way by the addition of electrochemical control and used to monitor the electrochemically induced solution-phase desorption of octadecanethiol (C18S) from a gold surface as well as the electrochemical polymerization of polypyrrole (PPY) on a gold surface. The experimental results obtained by the joint technique compare favorably with those obtained using SPR and QCM independently. The combination allows us to measure simultaneously the optical and acoustic properties of these materials as they interact with the metallic surface. While SPR and QCM have similar resolution and are both able to follow deposition in real time, there are distinct advantages to the simultaneous measurement. These advantages allow one to (1) test the validity of the governing equations often used to analyze data collected using the two techniques, bringing to light weaknesses in the assumptions inherent in these equations, (2) calculate interfacial density and refractive index values in a system where the bulk values are known and the physical state of the adsorbed material is similar to that of the bulk, (3) show that the viscoelastic properties of an adsorbed material change significantly as the material desorbs from an interface, and (4) observe the evolution in the electronic and chemical properties of a conducting polymer film as it is being deposited while precisely monitoring the mass of the deposited film.

Stable silicon dioxide (silica, SiO2) films on noble metals were synthesized using a novel sol−gel technique. Surface plasmon resonance (SPR) spectroscopy was used to compare the stability of silica films generated by this sol−gel technique with those deposited by using thermal evaporation, in the presence of PBS buffer. These films were later chemically functionalized with various reactive groups as a test for their versatility and usefulness in sensoric applications. A surface grating enclosed in a high-pressure and elevated temperature cell was used in the investigation of polymer brushes while SPR coupled with fluorescence detection schemes was used in the Kretschmann prism configuration to monitor DNA hybridization interactions.