title: Surface modification of ultra thin poly (epsilon-caprolactone) films using acrylic acid and collagen.
abstract: Poly (epsilon-caprolactone) (PCL) has been used as a bioresorbable polymer in numerous medical devices as well as for tissue engineering applications. Its main advantage is its biocompatibility and slow degradation rate. PCL surface, however, is hydrophobic and cell-biomaterial interaction is not the best. We attempt for the first time to modify an ultra thin PCL surface with collagen. The PCL film was prepared using solvent casting and biaxial stretching technique developed in our laboratory. This biaxial stretching produced an ultra thin PCL 3-7 microm thick, ideal for membrane tissue engineering applications. The PCL film was pretreated using Argon plasma, and then UV polymerized with acrylic acid (AAc). Collagen immobilization was then carried out. The modified film surface was characterized by Fourier Transform Infrared (FT-IR) and X-ray Photoelectron Spectroscopy (XPS). Water contact angles were also measured to evaluate the hydrophilicity of the modified surface. Results showed that the hydrophilicity of the surface has improved significantly after surface modification. The water contact angle dropped from 66 degrees to 32 degrees. Atomic Force Microscopy (AFM) showed an increase in roughness of the film. A change from 46 to 60 nm in the surface morphology was also observed. The effect of cells attachment on the PCL film was studied. Human dermal fibroblasts and myoblasts attachment and proliferation were improved remarkably on the modified surface. The films showed excellent cell attachment and proliferation rate.
authors.affiliation: Department of Mechanical Engineering, Centre for Biomedical Materials Applications and Technology (BIOMAT), National University of Singapore, Kent Ridge, Singapore 119260, Singapore.
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Cheng
authors.forename: Swee-Hin
authors.initials: SH
authors.lastname: Teoh
mesh_terms: D000179:Acrylates / Q000737:chemistry*; D000327:Adsorption; D002208:Caproates / Q000737:chemistry*; D002448:Cell Adhesion / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods*; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003094:Collagen / Q000737:chemistry* / Q000648:ultrastructure; D005347:Fibroblasts / Q000166:cytology* / Q000502:physiology; D006801:Humans; D007783:Lactones / Q000737:chemistry*; D008422:Materials Testing; D008567:Membranes, Artificial; D008968:Molecular Conformation; D032446:Myoblasts / Q000166:cytology* / Q000502:physiology; D013499:Surface Properties; D017155:Wettability
chemical_list: D000179:Acrylates; D002208:Caproates; D020099:Coated Materials, Biocompatible; D007783:Lactones; D008567:Membranes, Artificial; C121056:caprolactone; D003094:Collagen; C036658:acrylic acid