Development of nanocomposite polymer filaments with anti-inflammatory properties for 3D printing as bone substituent

Abstract

There is a growing number of bone injury cases worldwide requiring effective surgical procedures. Biomaterial nanocomposites are promising materials for bone tissue engineering due to the possibility of allying, through the appropriate choice of a polymer matrix and inorganic filler, biocompatibility, bioabsorption and mechanical resistance properties to be compatible with bone structures. Recently, rapid prototyping techniques (3D printing) have become popular, making possible to fabricate bone implant structures with complex shapes at a suitable scale. One of the main techniques with equipment already available in the national market is that based on polymer filaments melting. However, pure polymer filaments are limited due to the lack of functional, biological properties. This project has as main objective the development of functional osteointegratable nanocomposite filaments suitable for melt 3D printing, which should hold adequate mechanical properties, aiming at tissue engineering and regenerative medicine applications. These nanocomposites filaments will be produced from PLA (poly(lactic acid), biocompatible and biodegradable polymer), nanohydroxyapatite (inorganic phase necessary for bone tissue regeneration) and anti-inflammatory drug-intercalated layered double hydroxides (naproxen). The nanocomposites will be obtained by extrusion and detailed studies on the interaction between these constituents, seeking parameters optimization for 3D printing, will be conducted. Characterizations will be performed by XRD, FTIR, TG / DTG, SEM, TEM, mechanical tests (tensile strength, compression, shear and torsion), evaluation of cell differentiation, cytotoxicity, biocompatibility, immune response (in vitro assays) and drug release studies.