Biomimetic and Bioresponsive Formation, Activity and Degradation (BBFAD) of Biomedical Materials

In nature, biological materials are continuously formed, remodelled and destroyed by a variety of biomolecules, which cells produce for accomplishing specific targets. In their activity, these biomolecules respond to and influence the surrounding environment. Specifically, biochemicals and materials influence each other's activity bidirectionally; for example, cells migrate through solid tissues by destroying destroying, the extracellular matrix through the action of enzymes; however, the production of these enzymes is modulated by a number of factors, part of which are released by the matrix during its degradation. After migration has taken place, a new matrix may be laid down; this action is not necessarily performed by the same kind of cells: e.g. in bone there are cells specialized in matrix destruction (osteoclasts), while others care of matrix deposition (osteoblasts). In the vast majority of cases, a range of different enzymes are employed for remodelling (degrading, producing, transforming) materials and modulating their activity.The present proposal deals with the molecular design of new materials for biomedical applications. Specifically, we target materials in the form of soft solids (hydrogels) or colloids (objects with sub-micron dimensions), which can be used for replacing missing tissues, releasing pharmacologically active compounds and, in a broader picture, promote regeneration phenomena.In these areas there is a specific need of developing materials with more controlled interactions with the biological environment. Inspired by natural biomaterials, we aim to provide bioresponsive and/or biomimetic character to them in each phase of their application: formation, activity and degradation.More in particular, we target biocompatible materials with specific functions that, in response to biological stimuli or mimicking biological processes, a) can be formed at the site of application, b) provide a specific activity and c) are finally degraded to non-toxic, excretable products, for possibly being replaced by natural, functional tissues.As a common denominator, most generally we will be focusing on the use of enzymes, either for providing our materials with responsiveness to enzymes occurring in the conditions of application, or for conferring to them a specific biomimetic function based on enzymatic acitivity.