Synthesis of Mesoporous Silica Spheres for Controlled Biomolecule Delivery
Inorganic silica has become attractive as a biomaterial because of its biocompatibility and excellent ability for functionalization through a broad range of chemical and physical methods. In particular, spherical mesoporous silica spheres have been studied as hosts for immobilization of biomolecules, and as vehicles for gene and drug delivery. A novel method for preparing mesoporous silica spheres from commercial silica colloid will be presented. This mesoporous material mainly aimed for nasal delivery of drugs/vaccines, which has been an area of interest for the pharmaceutical industries in recent years to overcome the alarming pattern of unsafe injection practices and the poor availability of orally administered and injectable vaccines.
In the present work, a novel synthesis of mesoporous silica spheres at the sub-micrometer and micrometer scale (0.5 to 1.6 μm) with a tailored pore size (14.1 to 28.8 nm) has been developed by using a simple electrolyte and inexpensive commercial inorganic silica. The influences of synthesis conditions on the formation of the mesoporous silica spheres were systematically investigated. This novel method is easily scalable and offers a great flexibility in tuning or tailoring the pore size, to produce large quantities of mesoporous silica spheres for potential use in bio-nanotechnology, drug delivery and inorganic adsorbent applications. Adsorption of protein onto these particles and the in vitro release profile will be discussed. Moreover, the immobilization of protein within the mesoporous silica via thiol coupling to the functionalized silica surface has also been investigated. This conjugation can protects protein against degradation and enables controlled release.