Fabrication of biphasic constructs using melt electrowriting (MEW) and extrusion based 3D printing
Supervisor: Sonja Kuth, Prof. Aldo R. Boccaccini
Hydrogels, that are non-toxic, bioactive, and biodegradable, can be used to mimic the extra cellular matrix (ECM) to form tissue-like structures . Polymers used for hydrogel processing are either components of the extracellular matrix or have similar macromolecular properties and therefore allow cellular interaction for tissue formation by providing a surrounding of endogenous signals . Hyaluronic acid (HA) is a naturally derived polymer that is a component of the native ECM and therefore omnipresent in the human body . Melt electrowriting (MEW) is an additive manufacturing technique to fabricate scaffolds made from fibers on a microscale using the biodegradable polyester poly(𝝐-caprolactone) (PCL) . By taking advantage of the mechanical support of PCL’s thermoplastic structure and the biological functionalization by the HA-hydrogel phase, the benefits of both phases can be combined in an advanced biphasic scaffold . In this thesis, we aim to combine extrusion 3D printing of an HA-based hydrogel with melt electrowriting (MEW) to fabricate biphasic constructs for soft tissue engineering applications.
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