Sustainable Electrical Responsive Scaffolds

Tridimensional (3D) porous structures, referred to as scaffolds, are widely used in biomedicine, as support to cell adhesion and growth, leading to cell differentiation and tissue regeneration; electrically conductive scaffolds have specific applications, as some tissues (musculoskeletal, neural and cardiac tissues) are positively stimulated by electricity. Generally conductive 3D scaffolds are made of synthetic polymers (PPy, PEDOT, PANI); there is however growing interest in developing materials from natural sources, for them to have reduced impact on the environment. Here, we discuss the most important reports in electrically conductive scaffolds prepared from natural and/or renewable sources; the natural polymers include chitosan, cellulose, hyaluronic acid, collagen, alginate and silk-derived materials. As these compounds are not conductive, they were modified with the addition of either the conductive polymers mentioned above, conductive carbon in different forms (graphite, graphene, etc.) or metallic nanoparticles; in some cases, a combination of these additives was explored, to study possible synergistic effects. The literature available on this topic confirms the potential of these sustainable materials for specific biomedical applications. Future investigations should focus on the use of sustainable materials also as conductive additives. Moreover, applications in the field of 4D printing should also be considered.