Mesoporous silica nanoparticles: nano-dimensional but powerful

Mesoporous silica is a type of colloidal silica, obtained by condensation of silica precursors into ordered mesostructure using a template-assisted sol-gel mechanism. According to the International Union of Pure and Applied Chemistry (IUPAC), meso materials have a pore size in a range from 2 to 50 nm. Mesoporosity also enriches material with a high surface area (>1,000 m²/g) and large pore volume (>1 cm³/g). The introduction of organic groups within the silica framework or onto the silica surface endows materials with countless combinations of properties, including control of charge and silanol density. Additionally, particles can be constructed with hollow, magnetic or quantum dot cores. Particularly interesting opportunities exist for designing multifunctional nanosystems through selective modifications of the external surface and the surface inside the mesopores, loading and entrapping cargo molecules with pore-capping molecules or nanoparticles, for achieving stimuli-responsive cargo delivery.