Fabrication of core-shell latex spheres with CdS/polyelectrolyte composite multilayers

Core-shell latex spheres with CdS/polyelectrolyte composite multilayers have been fabricated via a layer-by-layer (LbL) self-assembly approach. The −SO3− and −NH3+ polar groups in polyelectrolytes (PSS and PAH) acted as the coordination sites for cadmium ion adsorption, and nanosized CdS particles were successfully grown in situ at these sites with the release of S2− ions from thioacetamide. The existence of CdS nanoparticles in polyelectrolyte multishells were confirmed by ζ-potentials, UV-vis and fluorescence spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM) measurements. Such hybrid core-shell latex spheres may find applications in biological fluorescence assay areas.