Photochemically and Electrochemically Triggered Au Nanoparticles Sponges

Stimuli-triggered wettability of surfaces and controlled uptake and release of substrates by smart materials are essential for drug delivery and microfluidic control. A composite sponge consisting of bis-aniline-bridged All nanoparticles (NPs), functionalized with photo-isomerizable nitrospiropyran/nitromerocyanine that includes selective imprinted molecular recognition sites for N,N'-bis(3-sulfonatopropyl)-4,4'-bipyridinium (PVS) was electropolymerized on a Au electrode. The system is triggered by photonic and/or electrical signals to yield four different states exhibiting variable binding/release capacities for PVS and controlled wettability of the surface. The electrical/optical uptake and release of PVS to and from the Au NPs sponge, respectively, is followed by CdSe/ZnS quantum dots, acting as an auxiliary photonic label.