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Funing Yan

Publications and source records attributed to Funing Yan.

3 recordsLinked to original sources
PubMed2006

Hole-enhanced Raman scattering.

Stokes and anti-Stokes non-resonant hole-enhanced Raman scattering (HERS) spectra with high signal-to-noise ratio (S/N) are reported for the first time for aqueous phase R6G molecules adsorbed onto random nanoholes in thin gold films. Compared to conventional surface-enhanced Raman scattering from nanometric gold colloid particles, HERS exhibits higher strength gain, exceptional reproducibility, simple and reliable substrate preparation, and excellent mechanical stability. By correlating the hole density with Raman scattering gain, we determined optimum HERS gain for 50 nm diameter holes at approximately 100 holes/microm(2). Providing a Raman substrate with uniform "hot spots", we expect that HERS will make the quantitative Raman analysis of biological molecules possible.

Journal Article↗
PubMedDate not supplied

Synthesis and characterization of a photocleavable cross-linker and its application on tunable surface modification and protein photodelivery.

A heterobifunctional photocleavable cross-linker based on an o-nitrobenzyl ester moiety was synthesized. The cross-linker has N-hydroxysuccinimidyl and disulfide groups attached at each end and thus can anchor a protein to a gold-coated substrate surface. Steady-state spectroscopic studies suggest that the cross-linker undergoes a clean C-O fragmentation upon irradiation with a quantum yield of 0.1. Consequently, immobilized proteins (such as avidin or antibodies) on a substrate surface can be released efficiently (>95%) under UV irradiation (lambda > 300 nm) without degrading the protein functionality. We also demonstrated protein delivery via bioconjugation of protein molecules to a gold-coated atomic-force microscope (AFM) tip. When the proteins are photoreleased from the AFM tip, they are delivered to the substrate surface as protein clusters of uniform size. This has been confirmed using both AFM and fluorescence microscopy. The application of bioconjugation in this study opens a new avenue for tunable surface modification and controllable protein delivery in studies of biological systems on the nanometer scale.

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