Poly(esterurethane urea)s for Soft Tissue Engineering Applications: Evaluation of Biological Properties

P.C. CARACCIOLO; A.A.A. DE QUEIROZ; G.A. ABRAHAM

Ouro Preto, Minas Gerais, Brasil

Congreso; V Congresso Latino Americano de Orgaos Artificiais e Biomateriais; 2008

SLABO

The development of biodegradable and biocompatible segmented polyurethane (SPU) and polyurethane networks with labile moieties susceptible to hydrolysis in the polymer backbone has been a subject of considerable interest in recent years. The highly variable chemistry of SPU may be used to generate polymers that exhibit a wide range of physical and chemical properties. In this sense, a careful selection of monomers can lead to a biodegradable SPU whose properties can be tailored to many different biomedical applications. Depending on their mechanical properties, chemical composition and surface characteristics, biodegradable SPU can potentially be used for designing cardiovascular implants, drug delivery devices, injectable augmentation materials and tissue adhesives. Nowadays, the use of polyurethanes in tissue-organ regeneration scaffolds for replacement or repair of a wide range of biological tissues is an area of intensive research and some examples about their uses in medicine are articular cartilage repair, cancellous bone graft substitutes, artificial skin, cardiovascular tissue engineering, meniscal reconstruction and meniscal prostheses. The biological properties of two novel bioresorbable-aliphatic segmented-poly(esterurethane urea)s (SPUU) based on poly(å-caprolactone) diol, 1,6-hexamethylene diisocyanate, and two novel urea-diol chain extenders, are presented and discussed in this work. Macrodiol, chain extenders, and SPUU were synthesized and characterized in our laboratory. The biological interactions between the obtained materials and blood were studied by in vitro methods. The quantitative adsorption of human serum albumin and fibrinogen onto the polyurethane surfaces was studied by Surface Plasmon Resonance. Research on platelet adhesion and activation, as well as kinetics of thrombus formation is presented. The higher albumin and lower fibrinogen adsorption onto these SPUU samples, as well as the suppression of platelet activation, suggested the antithrombogenic behavior of these surfaces. From a material standpoint, a significant difference was observed in the proportion of CD62P expressing platelets on the SPUU coatings. The coated SPUU surfaces exhibited low non activated platelet adhesion. The results showed that the prepared SPUU are promising bioresorbable elastomers for soft tissue engineering applications.