Pirosa Alessandro

Supervisor: Prof. Federica Chiellini

Title: Preparation and characterization of micro/nanostructured tridimensional scaffolds based on renewable polymers for tissue engineering applications

Abstract: Polymeric materials employed in biomedical applications should possess multifunctional characteristics such as biocompatibility, bioactivity and suitable mechanical properties as they come in direct contact with body fluids in vivo. Additionally a polymeric system designed for tissue engineering applications, should also possess biomimetic architecture and support cell adhesion, proliferation and differentiation. Tissue-engineering applications are various, ranging from the regeneration of hard tissues like bone, cartilage, teeth, and soft tissues such as muscles and epithelia, thus there is an increasing need to develop new materials with tailorable properties. At present, there is an upsurge of interest in polymeric materials for biomedical applications obtained from natural and sustainable resources to limit the depletion of fossil resources. Moreover renewable polymers are often provided with inherent biocompatibility, biodegradability and bioactivity as a consequence of their natural origin. Aim of the present project is the design and the development of micro/nanostructured three-dimensional supports, based on renewable polymers and bioactive molecules, to use as scaffolds in tissue engineering applications and regenerative medicine. For this issue, novel biodegradable polymers from renewable sources, including polysaccharides, proteins, microbial natural polyesters and their derivates, will be investigated and, if necessary, chemically modified to assess their potential use as matrices for the production of three-dimensional scaffolds. These materials will be processed by means innovative techniques (e.g. computer aided wet-spinning, fused deposition modeling, electrospinning) in order to obtain predefined internal micro/nano-structures and external shapes. Moreover antibiotic agents, growth factors and drugs will be employed to provide the scaffolds with better functionality and bioactivity. Structural, chemical-physical and mechanical characterizations of the scaffolds will be performed to study the effects of processing on the materials properties, the internal structure, the porosity and the anatomic and mechanical matching of the scaffold with the target tissue. Scaffolds will be also submitted to cell culture experiments to assess the biological compatibility of the employed materials and their ability to support cell adhesion, proliferation and differentiation, depending on the application. Finally depending on the results gained from the in vitro evaluation, a selected number of the most promising scaffolds will be tested in preliminary in vivo investigations.