Cytotoxicity testing of poly(anhydride-co-imides) for orthopedic applications

The cytotoxicity of a series of poly(anhydride-co-imides) with osteoblast-like cells (MC3T3-E1) was evaluated. The imide component of the copolymers was based on trimellitylimidoglycine (TMA-gly), and the anhydride component was based on either sebacic acid (SA) or 1,6-bis(carboxyphenoxy)hexane (CPH). Cell adhesion and proliferation on surfaces of the polymer discs were observed by environmental scanning electron microscopy (ESEM). During the first 24 h of attachment, cells showed normal morphology when cultured on the various copolymers of CPH. Concurrently, the effects of polymer breakdown products on osteoblast-like cells were evaluated by studying their proliferation (cell numbers), viability (dye exclusion), and morphology (light microscopy). Cell cultures in the presence of these breakdown products resulted in normal morphologies and reached confluency after 7 days. This initial in vitro evaluation with osteoblast-like cells suggests that the poly(anhydride-co-imides) may be viable carriers for osteoblasts.