IPNs networks of pHEMA-PLA for use in Tissue Engineering

Abstract

Advances in modern medicine and engineering, combined with increased life expectancy, has allowed the development of biofabrication techniques and biomaterials, to improve the quality of life. These biomaterials must be able to mimic living structures, both in function and in form, being then possible to replace damaged tissues (Jardini et al, 2010). One area that studies the combination of biochemical engineering and integrated technologies of cells, materials, biology and medicine in order to create or regenerate tissue and / organ damage is the Tissue Engineering. This scientific field has motivated the development and improvement of materials to achieve this goal. Among the materials examined include ceramics, metals and polymers. However, metals and ceramics are not biodegradable and their processing is relatively limited, favoring the study of polymers for applications in regenerative medicine. Therefore, research on development, identifying and implementing durable conventional materials, have been conceptually modified by advances in the fabrication of biocompatible polymers, biodegradable and bioabsorbable (Jardini et al, 2010; Griffith, 2000) in applications as biomaterials. However, the development of biomaterials with specific characteristics and similar to the region which is being replaced is still a major challenge for researchers (Lunelle et al, 2010). Materials based on acrylates and lactones such as poly lactic acid and poly 2-hydroxy ethyl methacrylate(pHEMA) become well-studied (Lasprilla et al, 2011; Kubinová et al, 2010). The first, pHEMA offers the possibility of easy modification of the structure by simply replacing the acrylate component, being chemically adjustable in terms of hydrophilicity, pH and temperature. On the other hand, the second, the PLA has the advantage of being a hydrophobic polyester, which in vivo, degrades into non-toxic components. These features make copolymers of pHEMA-PLA highly interesting for a range of medical applications, ranging from controlled release systems of drugs to the fabrication of biodegradable surgical implants (Wolf et al, 2009). It is further that the combination of polyester with pHEMA in general is not well known and has been performed in few studies (Wolf et al, 2009). pHEMA-PLA copolymers can be obtained via the technique of vapor deposition (CVD). This technique is capable of synthesizing pHEMA linear polymers and crosslinked, from vapors of the monomer (HEMA) without the use of solvents or volatile, getting movies on a single processing step (Chan and Gleason, 2005). Therefore, this doctoral project aims to develop a new biofabrication process of pHEMA-PLA interpenetrating networks (IPNs) / copolymers for applications in tissue engineering by CVD. It is a step in the development of advanced polymers "clean", with appropriate stoichiometric compositions, molecular weights tunable, no additives and / or solvent waste. This is of paramount importance, indeed necessary, for polymers used in the biomedical field, since the presence of organic residues from the polymerization process matrices processed by solvent, can decrease the activity of biological factors embedded in it, thus promoting an inflammatory response of the tissue in vivo. The copolymers are obtained in a biorreactor linked to biofabrication system developed during the student's dissertation Marcele Fonseca Passos. This project will be developed at the Laboratory of Optimization, Design and Advanced Control (LOPCA) coordinated by Prof. Dr. Rubens Maciel Filho, in partnership with the Federal University of Para and the National Institute of Science and Technology-BIOFABRIS.