Biomaterials & scaffolds

At the Centre for Translational Bone, Joint and Soft Tissue Research we focus on the development of new biomaterials for the regeneration of tissue defects and innovative techniques to manufacture scaffolds for tissue engineering applications. We focus on both synthetic implant materials such as calcium phosphates as well as on materials of biological origin, for example hydrogels based on collagen or alginate.

Biopolymers and hydrogels

Hydrogels are defined as soft, three-dimensional networks of polymers that can hold considerable amounts of water. They therefore resemble the soft tissue of our body and can be used in tissue engineering applications as an artificial matrix that hosts living cells – mimicking a living tissue! We use a variety of different biopolymers such as alginate, chitosan or collagen to develop hydrogels as cell-carrier for different tissue types.

Alginate-scaffolds with aligned pores, for example, have been developed to help regenerate neuronal structures. Another example are chitosan-based scaffolds that could help to treat cartilage defects [Flock]. Furthermore, hydrogels are an important basis for biofabrication of complex shaped scaffolds [Biofabrication].

Calcium phosphates

Calcium phosphate ceramics, and calcium phosphate cements in particular, possess outstanding properties when it comes to regenerate bone defects: their chemical composition resembles the inorganic part of the natural bone, which is the reason for their excellent biocompatibility. By carefully varying their composition we develop bone cements that are specifically adapted to the needs of patients suffering from specific diseases. For example, we substituted calcium phosphate cements with therapeutically active ions to help the regeneration of osteoporotic bone defects [TR79 M2].

Another focus of our work is the application of bone cements as drug- and protein-delivery systems: with such systems drugs and growth factors are delivered directly in the tissue defect area and help the local tissue regeneration.

Calcium phosphate cements can also be shaped using biofabrication techniques to obtain complex and functional scaffolds for tissue engineering applications [Biofabrication].

Composites

Composites allow combining the positive properties of different biomaterials by joining them in a new material. For example, we use a biomimetic mineralisation process to obtain mineralised collagen – a composite that closely mimics the natural bone structure and is therefore well-suited as scaffold material to regenerate bone defects.

Based on mineralised collagen we’re working on a new approach: in situ tissue engineering. The idea is to load scaffolds with growth factors that are released as soon as the scaffold has been implanted in the body and then attracts specific cell types to migrate into the artificial structure. Again, this could help to fast and fully regenerate bone defects [TR79 M4].