New Approaches for Biocompatibility Testing Using Cell Culture

We are proposing two modified assays for biocompatibility testing which analyze the effects of cytotoxic substances leached from a biomaterial in cell culture. The biocompatibility of two vascular prostheses made of polytetrafluoroethylene was analyzed using the modified assays. One test, the "fluid medium assay" was modified by using small pieces of graft glued to a screening lid, thereby reducing the possibility of mechanical injury to cultured cells by free fragments of the tested biomaterial. Another test, the "cell inhibition assay" was modified in that the biomaterial to be tested was ground into small pieces while at very low temperature. The measure of cell toxicity used was the effect on DNA replication. Our results suggest that these modified assay methods can be used to evaluate the biocompatibility of biomaterials.