ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Collagen-grafted ultra-high molecular weight polyethylene for biomedical applications
Jindřiška Bočková, Lucy Vojtová, Radek Přikryl, Jan Čechal, and Josef Jančář
Institute of Materials Chemistry, Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, 612 00 Brno, Czech Republic
Received: 14 November 2007 Revised: 16 April 2008 Accepted: 28 April 2008
Abstract: A novel material for hard tissue implants has been prepared. The ultra-high molecular weight polyethylene (UHMWPE) was grafted
with collagen I, to improve its biocompatibility with soft tissue in case of its usage in bone engineering. Before collagen
immobilization, commercial grade UHMWPE was treated with air plasma to introduce hydroperoxides onto the surface and subsequently
grafted with carboxylic acid to functionalize the surface. Acrylic acid and itaconic acid were used for surface functionalization.
After graft polymerization of carboxylic acids, collagen was immobilized covalently through the amide bonds between residual
amino and carboxyl groups in the presence of water-soluble carbodiimide/hydroxysuccinimide cross-linking system. Each step
of modification was characterized using spectroscopic (EPR, ATR-FTIR, and XPS), microscopic (SEM and CLSM), and contact angle
measurement methods. The experimental results showed that plasma treatment led to a generation of free radicals on the UHMWPE
surface resulting in the formation of unstable hydroperoxides. These reactive species were used to graft unsaturated carboxylic
acids onto UHMWPE. Consequently, collagen was grafted via the-NH2 and-COOH reaction. The obtained experimental data along with microscopic observations confirmed the success of graft poly-merization
of itaconic as well as of acrylic acid and collagen immobilization onto the UHMWPE surface.
Keywords: ultra-high molecular weight polyethylene - collagen immobilization - biocompatibility - free radical - cold plasma
Full paper is available at www.springerlink.com.
Chemical Papers 62 (6) 580–588 (2008)