Novel non-cytotoxic, bioactive and biodegradable hybrid materials based on polyurethanes/TiO2 for biomedical applications.

Titanium compounds have demonstrated great interfacial properties with biological tissues whereas a wide variety of polyurethanes have also been successfully probed in medical applications. However, studies about hybrids based on polyurethanes/TiO for medical applications are scarce. The aim of this work is to design novel biodegradable hybrid materials based on polyurethanes/TiO (80percent organic-20percent inorganic)and to perform a preliminary study of the potential applications in bone regeneration. The hybrids have been prepared by a sol-gel reaction using titanium isopropoxide as precursor of the inorganic component and polyurethane as the organic one. A series of polyurethanes has been prepared using different polyesters glycol succinate as soft segment, and 1,6-diisocyanatohexane (HDI)and butanediol (BD)as linear hard segment. The spectroscopy techniques used allow to confirm the formation of the required polyurethanes by the identification of bands related to carboxylic groups (-COOH), and the amine groups (-NH-), and also the Ti-OH bonds and the bonds related to the interconnected network between the inorganic and the organic components from hybrids. The results from SEM/EDS show a homogeneous distribution of the inorganic component into the organic matrix. The nontoxic character of the hybrid (H400)was probed using MG-63 cell line with over 90percent of cell viability. Finally, the formation of a hydroxyapatite layer in the material surface after 21 days of soaking in SBF shows the bioactive character.