Preparation of Photo-Sensitive Degradable Polymeric Nanocapsules from Dendrimer Grafted Nano-Silica Templates

Abstract

The poly-hydroxylated photo-sensitive degradable polymeric nanocapsules were prepared by the condensation of the A2-type monomer 4, 4'-Azobenzene dibenzoyl chloride (ADC) and the B3-type monomer triethanolamine (TEA) from the sacrificial nano-silica templates by a divergent approach. After the dendrimer molecules grafted on the silica nanoparticles were cross-linked with ADC, which is both the monomer and the cross-linker in this approach developed subsequently, the silica templates were removed by being etched with hydrofluoric (HF) to produce the photo-sensitive degradable polymeric nanocapsules. The hollow structure of the polymeric nanocapsules with the inner diameter about 20-100 nm is characterized by transmission electron microscopy (TEM). The photo-responsive behavior of the nanocapsules is confirmed by UV-Vis spectroscopy.