Síntese, caracterização e avaliação do comportamento degradativo de híbridos poli (álcool vinílico)/vidro bioativo imersos em meio aquoso

Abstract

Tissue engineering combines the principles of engineering and biology to repair damaged tissue. One of the challenges in the tissue engineering is associated with the development of suitable scaffold materials that can act as templates for cell adhesion, growth andproliferation. The scaffolds may present adequate pore size and interconnectivity to promote cell in-growth, good biocompatibility and kinetic of degradation where is possible to control scaffold degradation to match the ratio of replacement by new tissue. Microporous compositeof biodegradable polymers with inorganic bioactive glasses are of particular interest in tissue engineering, where the ceramic phase can improve or fulfill the osteogenic features, moreover the ratio of degradation is able to be tailored by polymer molecular weight or crosslink density. Other criteria which must be considered in the design of biomaterials include the provision of adequate mechanical strength. The extraordinary mechanical properties of carbon nanotubes (CNT) make them particularly attractive as reinforcements in composite materials. However the effective utilization of CNT in composite applications depends strongly on their ability to be dispersed individually and homogeneously within a matrix. In this work wereproduced hybrids by the sol-gel process. To prepare the hybrids, PVA was dissolved in water and the BaG solution was obtained by mixing deionized water, TEOS, TEP and CaCl2 in order. Both solutions were prepared with amounts of BaG with 58wt.% of SiO2, 33wt.% ofCaO and 9wt.% of P2O5 in solution of PVA, respectively. Then, surfactant, catalyst for gelation and glutaraldehyde, as crosslinker agent were added to the previously prepared solution. Samples were submitted for degradation study by soaking into deionized water at 37 oC for periods of time up to 21 days. In order to investigate the structure, PVA-derivedhybrids were characterized by SEM, weight loss and cell biocompatibility assay. In addition, were produced macroporous hybrids PVA-BaG reinforced with COOH functionalized multi wall CNTs. The results indicated gradual decrease in the weight loss with the increase in theratio of glutaraldehyde agent used and cell viability obtained for large soaking time at the tested medium. The good dispersion of the functionalized CNTs and bonding to the polymeric/ceramic matrix strongly improved the mechanical strength of the hybrids.