Porous methacrylate scaffolds: supercritical fluid fabrication and in vitro chondrocyte responses

This paper describes a method of foaming a polymer system comprising poly(ethyl methacrylate)/tetrahydrofurfuryl methacrylate (PEMA/THFMA), characterisation of the resulting porosity and use of the foam for chondrocyte culture. The potential for this polymer system to support cartilage repair has been investigated previously, both in vivo and in vitro. PEMA/THFMA foamed created using supercritical carbon dioxide were characterised using scanning electron microscopy, mercury intrusion porosimetry and helium pycnometry. Foams were found to be 82% porous with open porosities of 57%. The mean pore diameter was found to be 99+60 microm. Bovine chondrocytes seeded directly onto the surface of the foamed and unfoamed PEMA/THFMA demonstrated lower proliferation on the foamed material, greater retention of the rounded cell morphology and increased glycosaminoglycan synthesis. In conclusion, this study has shown that a porous PEMA/THFMA system can further enhance the ability of the material to support chondrocytes in vitro. However, further modifications in processing are necessary to determine optimum conditions for cartilage tissue formation.