In Vitro Cytotoxicity Studies of Novel Mesoporous Inorganic Polymers

Bone is one of the most frequently transplanted tissues with 8 million surgical procedures performed annually in the United States alone. The leading practice is the use of autologous graft. However, given the high demand for bone grafts and the short supply of autologous graft, new biomaterial alternatives are needed that are bio-inductive, bio-conductive, and biocompatible. We focus on a new breed of potential bone grafts: Inorganic polymers. Inorganic polymers are X-ray amorphous polymers that exhibit a hierarchical architecture similar to that of cortical bone: nanogranular and mesoporous. We examine the bio-inductivity via biomineralization experiments. We evaluate the bio-conductivity by studying the cell-wall interactions of mouse fibroblast cells. Our preliminary results have shown that inorganic polymers are bio-inductive. Calcium phosphate crystals were observed after immersion of inorganic polymers in simulated body fluid solution. Preliminary results have also shown that inorganic polymers are resorbable as a decrease in weight was observed after accelerated biodegradation experiments. We will show the results of additional biomineralization and biodegradation studies. Moreover, we will examine the potential of inorganic polymers to promote fibroblast cells' adhesion and migration. These results are important to yield novel bone scaffolds for bone tissue regenerative engineering.