DEGRADATION PRODUCTS OF POLY(ESTER-ETHER-ESTER) BLOCK-COPOLYMERS DO NOT ALTER ENDOTHELIAL METABOLISM IN-VITRO

In this paper we report experimental results from specific biocompatib ility tests on two different classes of tri-block poly(ester-ether-est er) copolymers, namely lon-caprolactone-oxyethylene-epsilon-caprolacto ne) and copoly(L-lactide-oxyethylene-L-lactide). In particular, the hu man umbilical vein endothelial cells (HUVEC) metabolism has been studi ed in the presence both of the copolymers and of their hydrolytic brea kdown products. The release of prostacyclin (PGl(2)) and angiotensin I I (All) has been measured at different times for copolymers with diffe rent composition and hydrophilicity. The results obtained seem to indi cate that the block copolymers of both series do not alter the PGI, an d All release by HUVEC populations in vitro. Similar results are found also after a prolonged contact between the cells and the hydrolytic b reakdown products of the copolymers. Furthermore, some of the copolyme rs studied significantly stimulate the release of either PGI, or All. This finding might point towards the use of these copolymers as bioact ive materials in the field of cardiovascular devices.