Preparation of lotus-leaf-like structured blood compatible poly(ε-caprolactone)-block-poly(l-lactic acid) copolymer film surfaces

Abstract

Lotus-leaf-like structured poly( -caprolactone)-block-poly(l-lactic acid) copolymer (PCL-b-PLLA) filmscast using the solvent–nonsolvent casting method. PCL-b-PLLA was synthesized by the well-knowncopolymerization process, and was confirmed by1H NMR analysis. The molecular weight of the syn-thesized PCL-b-PLLA was measured by gel permeation chromatography (GPC). The number-average(Mn), weight-average (Mw) molecular weights and polydispersity (Mw/Mn) were 3.9 × 104, 5.1 × 104,and 1.3, respectively. PCL-b-PLLA films were cast in vacuum conditions with various nonsolvent ratios.Tetrahydrofuran (THF) was used as solvent and ethanol was used as nonsolvent. Surface hydrophobic-ity was confirmed by the water contact angle. The water contact angle was increased from 90.9◦± 4.2◦to 130.2◦± 3.6◦. Water contact angle was found to be influenced by surface topography. The preparedfilm surfaces were characterized by scanning electron microscopy (SEM). Changes in crystalline propertywere characterized by X-ray diffraction (XRD). Platelet adhesion tests of the modified PCL-b-PLLA filmsurfaces were evaluated by platelet-rich plasma (PRP) and whole blood. Cell adhesive behavior on themodified film surfaces was evaluated by fibroblast cell culture. The prepared lotus-leaf-like structuredfilm surfaces exhibited reduced platelet adhesion and an increased fibroblast cell proliferation ratio.