Preparation and structural characterization of nanoporous silica/magnesium(II)-whitlockite composite particles

The preparation of particles composed of nanoporous silica (NS) and Mg2+-whitlockite (Mg-WH) would provide valuable insights for designing particles for biomedical applications. In this study, NS and Mg-WH composite particles were successfully synthesized. The addition of chitosan during synthesis possibly promoted the crystallization of calcium phosphate phases in the composite particles. Pore size distribution analysis of the particles showed a maximum at 3.2 nm. Investigating the adsorption of methylene blue onto the particles in a phosphate buffer (pH 7.4) showed that the saturated adsorption amount of methylene blue on the particles was significantly higher than that on commercial hydroxyapatite. The composite particles provided important results for potential applications as drug carriers for bone regeneration and repair.