Impacts of stereoregularity and stereocomplex formation on physicochemical, protein adsorption and cell adhesion behaviors of star-shaped 8-arms poly(ethylene glycol)-poly(lactide) block copolymer films

Biodegradable stereocomplex film exhibiting soft and stretchy character was prepared by simply blending between enantiomeric 8-arms poly(ethylene glycol)-block-poly(l-lactide) (8-arms PEG-b-PLLA) and 8-arms PEG-b-PDLA copolymers with star-shaped structure. The stereocomplex film exhibited higher T_g and PLA crystallinity than those of original copolymer films. Effects of stereoregularity and stereocomplexation on protein adsorption and L929 cells attachment/proliferation behaviors onto the films were analyzed from the viewpoint to design a new class of implantable soft biomaterial. The stereocomplex film was found to exhibit large amount of protein adsorption than original films. Furthermore, cell attachment efficiency and proliferation rate on the film were significantly enhanced by stereocomplexation. This stereocomplex material is expected to be applicable as degradable temporary scaffold for soft tissue regeneration. Consequently, it was indicated that the stereocomplex formation could be proposed to be a novel method to control the protein- and cell-adhesive properties of biodegradable matrix composed of PEG-PLA copolymer.