Patterning of a random copolymer of poly[lactide-co-glycotide-co-(epsilon-caprolactone)] by UV embossing for tissue engineering

The random copolymer, poly[lactide-co-glycotide-co-(epsilon-caprolactone)] (PLGACL) diacrylate was prepared by ring-opening polymerization of L-lactide, glycolide, and epsilon-caprolactone initiated with tetra(ethylene glycol). The diacrylated polymers were extensively characterized. With a UV embossing method, these copolymers were successfully fabricated into microchannels separated by microwalls with a high aspect (height/width) ratio. The PLGACL network films showed good cytocompatibility. Varieties of microstructures were fabricated, such as 10 x 40 x 60, 10 x 80 x 60, 25 x 40 x 60, or 25 x 80 x 60 microm(3) structures (microwall width x microchannel width x microwall height). The results demonstrated that smooth muscle cells (SMCs) can grow not only on the microchannel surfaces but also on the surfaces of the microwall and sidewall. The SMCs aligned along the 25 microm wide microwall with an elongated morphology and proliferated very slowly in comparison to those on the smooth surface with a longer cell-culture term. Few cells could attach and spread on the surface of the 40 microm wide microchannel, while the cells flourished on the 80 microm, or more than 80 microm, wide microchannel with a spindle morphology. The biophysical mechanism mediated by the micropattern geometry is discussed. Overall, the present micropattern, consisting of biodegradable and cytocompatible PLGACL, provides a promising scaffold for tissue engineering.