Studies of Surface-Adsorbed Fluorescently Labeled Casein and Concanavalin A Using Surface Plasmon-Coupled Emission
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We report the use of surface plasmon-coupled emission (SPCE) as an analytical tool to study the photophysics of surface-adsorbed fluorescently labeled proteins. The study uses plasma etching of PMMA surface followed by deposition of poly(diallyldimethylammonium chloride) (PDDA) for surface protein detection. PDDA increases the overall amount of the captured protein and also promotes dye aggregation. The photon-sorting properties of the SPCE process allows for wavelength separation of the individual components from the protein–dye aggregates. This has been exploited to study the fluorescence emissions from casein labeled with fluorescein isothiocyanate and concanavalin A labeled with tetramethylrhodamine. Based on the current findings, the proteins can be used to measure background fluorescence or to monitor the microenvironments in fluoroimmunoassays on SPCE substrates.
KeywordsSurface plasmon-coupled emission Protein monolayers Silver films Plasma etch Spectral resolution
Surface plasmon-coupled emission
Surface plasmon resonance
- Con A
Layer by layer
This work was made possible by funding from the following grant award: NSF-BES 0517785.
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