Synthesis of Particle and Pore Size-Tunable Mesoporous Silica Nanoparticles by Simultaneous Emulsion Radical Polymerization and Sol-gel Chemical Reactions

Silica mesoporous nanoparticles (MSNs) have received widespread interest because of their wide range of applications. A new approach was developed for preparing MSNs that is able to improve loading of poorly water-soluble drug and the dissolution rate for oral administration. The synthesis method shares features of simultaneous emulsion polymerization of methacrylate ester and sol-gel of silica precursor in n-heptane/water interface. The MSNs were characterized by DLS, FE-SEM, XRD and BET. Finally, curcumin was loaded into mesoporous nanoparticles by solid dispersion method and the amount of loading was detected by UV spectroscopy. The pore size and particle diameter were drastically affected by changing the methyl methacrylate concentration and the oil/water ratio, respectively. FE-SEM micrographs showed that MSNs had a nearly spherical shape. BET results demonstrated pore sizes range from 4 to 8 nm and specific surface area range from 747 to 546 m²/g. DLS results indicated that different volumes of n-heptane resulted in different particle sizes from 25 to 100nm. Curcumin loading was 28% w/w in MSNs with the pore size f 7 nm. These results indicated that the MSNs could provide a new platform for delivering poorly water-soluble phytochemicals.