Molecular and nanoscale engineering of porous silica particles for drug delivery

The advantageous bulk and surface properties of porous silica have made them ideal matrices for both stabilization of drugs as well as providing better control of drug release properties. The aim of this chapter is to provide a summary of the current knowledge on the molecular and nanoscale engineering of porous silica particles for drug delivery. Synthesized from the typical wet chemical process based on sol-gel techniques, these porous nanocarriers offer diverse opportunities for distinct design of structures, surface/interfacial properties, functional synergies, and so forth. Of pivotal importance is the tuning of the host-guest interactions in the confined nanopore space for accommodating various drugs or biomolecules with intrinsically different properties including molecular size, charging behavior, and polarity. Optimization of loading methods in solution or construction of gated systems on the external surface are usually involved. New designs on the basis of incorporating bioadhesive polymers on the pore walls have also emerged. Novel dosage forms including printed formulations, orodispersible films, and lyophilized tablets have been generated for achieving the full potential of these nanocarriers. All these issues are reviewed and discussed in this chapter.