(715a) Copper and Its Alloy Nanostructures for Metal Enhanced /Quenched Luminescence

Enhanced
signal and photostability of luminophores, improved surface immunoassay and DNA detection, and enhanced wavelength-ratiometric sensing, amplified assay detection are few
examples of applications of metal enhanced luminescence.  On the other
hand, quenching resulted due to metallic nanoparticles are successfully
utilized for the improvement of homogeneous and competitive fluorescence
immunoassay, optical detection of DNA hybridization, competitive hybridization
assay and in optoelectronics.  In this work, metal enhanced/quenched
luminescence was explored at the vicinity of copper and its alloy
nanostructures. Silver copper alloy nanoparticles at different compositions
(x=100, 67, 50, 40, 10 and 0) were studied.  Silver-copper nanoparticles
of different composition were synthesized using the polyol process. It was
observed that the luminescence of dye was strongly dependent on the Ag-Cu
nanoparticles composition. Highest luminescence enhancement of dye Cy 3,
commonly used for biological applications, was realized at the vicinity of pure
silver nanoparticles. Enhancement effects were found to decrease as the
percentage of copper increases in nanoparticles, leading to the quenching of
fluorescence at the pure copper nanoparticles platforms. Signal manipulation of
luminescent dye using different composition alloy nanoparticles is expected to
extend it's application in different fields ranging from optoelectronics to
biological research.