Sol–gel derived carrier for the controlled release of proteins

Sol–gel derived porous silica carriers for the controlled release of proteins were synthesized using a room temperature process. The materials are intended to serve as both substrates for bone growth as well as to allow incorporated proteins such as growth factors to diffuse out and stimulate cell function and tissue healing. The data document that the in vitro release of trypsin inhibitor, a model protein of size similar to growth factors with documented effect in bone, was dose and time dependent during immersion up to nine weeks. The release pattern included an initially slow release, with further release occurring at a rate which is proportionate to the square root of time, an indicative of a diffusion-driven process.