Colloidal and spherical mesoporous silica particles: synthesis and new technologies for delivery applications

Continuous research in prominent fields such as biotechnology, biomedicine and nanopharmaceutics has brought the development of a widespread class of materials, and studies for mesoporous materials have been exponentially growing lately. The purpose of this review is to provide a useful guide for different materials, methods and configurations that have been reported in the last 5 years for the synthesis of spherical mesoporous silica particles (MSP), in the colloidal size range (1–1000 nm). MSP exhibit several limitations that must be overcome in order to enable their medical and clinical use. Surface modification of these particles will allow getting new promising characteristics of these materials, including better drug release control and biocompatibility improvement. These modified MSP could be potentially used in many biomedical applications, especially for drug delivery systems. Emphasis is made on the pore size, diameter and shape of the final particles since these parameters will establish key characteristics, i.e., drug delivery profile, loading capacity and efficiency.

Spreading the use of mesoporous silica particles in biomedicine is possible by the improvement of its inner characteristics through surface modification. This may be done by chemical functionalization or by coating with macromolecular layers or brushes, thus creating novel responsive core–shell hybrid composites to be used as carriers for drug delivery applications.