Surface modification of poly-L-lactic acid films by electrostatic self-assembly to promote vascular smooth muscle cells growth

Abstract

The intention of this study was to surface modify the poly-L-lactic acid (PLLA) film and evaluate the effects of the surfaces on the growth of vascular smooth muscle cells (VSMCs) in vitro. Collagen and hyaluronic acid (HA) were utilized as polycation and polyanion in this study. Layer-by-layer (LBL) self-assembly technique was used to lead to the formation of multilayer moleculer on the poly-Llactic acid (PLLA) film surfaces. Collagen/HA layers was overcasted coating on the PLLA surface after the activation layers by poly-(ethyleneimine) (PEI). The structure and morphology of the multilayer molecular were examined by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrophotometer and atomic force microscope (AFM), respectively. The ATR-FTIR analysis illuminated the presence of collagen on the PLLA surface. The AFM results showed the multilayer appeared on PLLA surface. The VSMCs were adopted to evaluate the cyto-compatibility of the modified PLLA films. It was found that the viability of VSMCs on the modified PLLA films were greater than that on original PLLA films and tissue culture plastic after ten days culture (p<0.05). Scanning electron microscopy (SEM) and laser scanning confocal microscopy (LSCM) data also confirmed the homogeneous results. These data suggest that collagen/HA coat can be successfully adopted in the surface modification of PLLA film through LBL technique, and also can enhance its cell compatibility.

Keywords

surface modification, poly-L-lactic acid (PLLA), electrostatic self-assembly, vascular smooth muscle cells (VSMCs)