Abstract
The subject of this study is to develop a novel approach to synthesize functional silica nanoparticles which have the abilities of NO storage and controlled release via RSNOs donor. The bifunctional reactive agent of 4- isocyanato- 4'-( 3,3'- dimethyl- 2, 4- dioxo- azetidino ) diphenyl methane (MIA) is employed to modify the surface of silica nanoparticles. Consequently, the isocyanate group of MIA reacts with silanol groups of silica nanoparticles while the azetidine-2,4-dione group of MIA demonstrates a high reactivity and selectivity with primary amine groups of chitosan. Furthermore, NO donors are formed by incorporation thiolglycolic acid into chitosan structure via exposed to acidified nitrite. Moreover, we also try the other different synthetic method by combining thiol group and chitosan first before amine group modifying silica nanoparticles. The chemical structures of nanoparticles are confirmed by FT-IR, ESCA, SLS, SEM, TEM. Additionally, we use Ellman assay to quantify the amount of thiol groups on modified silica nanoparticles, and the characterization of NO release is observed by Griess assay.The results presented here show that SCTNO particles can be more promising NO release system than SCSNO particles, the former demonstrate the NO storage of 0.17 μmol NO/ mg particle while the latter with 0.08 μmol NO/ mg particle.