Surface-enhanced raman scattering on dendrimer/metallic nanoparticle layer-by-layer film substrates.

摘要: In this paper, the fabrication, characterization, and application of unique layer-by-layer (LBL) films dendrimers metallic nanoparticles is reported. Silver (d = approximately 20 nm) are produced in solution by sodium citrate reduction incorporated into thin with generation 1 5 DAB-Am (polypropylenimine amino surface groups) LBL technique. The resulting nanocomposite characterized UV-visible plasmon absorption atomic force microscopy (AFM) measurements, employed as substrates for surface-enhanced Raman scattering (SERS) 2-naphthalenethiol. Through variation molecular size (dendrimer generation) concentration cross-linker used, well number layers produced, optical properties several different possible architectures studied. films, Ag shown to be effectively immobilized stabilized increased control over their spacing aggregation. Moreover, excellent SERS demonstrating significant enhancement capability. As expected, large electromagnetic signals found strongly dependent on interparticle coupling between neighboring nanoparticles. Finally, possibility detecting from intervening metal analyte molecules explored. It that although there decreases intensity increasing (as expected distance dependence SERS), still able function at these distances, thus offering developing sensors external chemically selective specific analytes.