Bio-based material formulation for extrusion printing by dityrosine crosslinking of unmodified casein

作     者：Haas, Sandra Götz, Friederike Hubbuch, Jürgen 

作者机构：Institute of Process Engineering in Life Sciences Section IV: Molecular Separation Engineering Karlsruhe Institute of Technology (KIT) Fritz-Haber-Weg 2 Karlsruhe 76131 Germany 

出 版 物：《Bioprinting》 (Bioprinting)

年 卷 期：2022年第28卷

基　　金：Baden-Württemberg Stiftung  BWS  (GB1001 GG653) 

主　　题：Alginate Bio-based material printing Casein Protein-based hydrogel Visible light-induced photopolymerization 

摘      要：In the development of new functional bio-based materials in the field of three-dimensional (3D) printing, visible light-induced dityrosine crosslinking gains increasing interest. In this context, most current bio-based materials and ink formulations rely on previously modified chemical substances with increased tyrosine availability. In contrast, we developed and characterized a photopolymerizable ink formulation for extrusion printing based on the unmodified and naturally occurring protein casein. Manufacturability of formulations containing protein, photoinitiating system, buffer and a thickening agent turned out to be a key factor for the ink development. In total, eight different thickening agents were assessed regarding their suitability to increase the viscosity of the ink formulation to expand the fabrication window for extrusion-based 3D printing. The mechanical properties of the ink formulation and hydrogel in presence of sodium alginate were further characterized and the macroscopic fabrication of auxetic structures consisting of up to 30 layers was achieved by applying extrusion-based printing. © 2022 Elsevier B.V.