Layer-by-layer assembly of biomacromolecules on poly(ethylene terephthalate) films and fiber fabrics to promote endothelial cell growth.

Abstract

Poly(ethylene terephthalate) (PET) film and PET vascular graft were modified by layer-by-layer (LBL) assembly of collagen and chondroitin sulfate (CS) to mimic the natural composition and structure of extracellular matrix. PET materials were first hydrolyzed to endow the surfaces with negative charge. Alternative assembly of positively charged collagen and negatively charged CS was then conducted in an LBL manner to produce biological multilayers. X-ray photoelectron spectroscopy confirmed the occurrence of hydrolysis and existence of collagen and CS. The stepwise layer growth on the PET film was monitored by UV-vis spectroscopy. The multilayers had sufficient stability to pass through the cell culture period (8 days). In vitro endothelial cell culture revealed that the incorporated biomacromolecules could significantly improve the cell attachment, proliferation, and viability. Cells showed more spreading morphology with preserved phenotype, as illustrated by scanning electron microscopy and factor VIII-related antigen immunocytochemistry, respectively.