title: Additive manufacturing of collagen scaffolds by three-dimensional plotting of highly viscous dispersions.
abstract: Additive manufacturing (AM) allows the free form fabrication of three-dimensional (3D) structures with distinct external geometry, fitting into a patient-specific defect, and defined internal pore architecture. However, fabrication of predesigned collagen scaffolds using AM-based technologies is challenging due to the low viscosity of collagen solutions, gels or dispersions commonly used for scaffold preparation. In the present study, we have developed a straightforward method which is based on 3D plotting of a highly viscous, high density collagen dispersion. The swollen state of the collagen fibrils at pH 4 enabled the homogenous extrusion of the material, the deposition of uniform strands and finally the construction of 3D scaffolds. Stabilization of the plotted structures was achieved by freeze-drying and chemical crosslinking with the carbodiimide EDC. The scaffolds exhibited high shape and dimensional fidelity and a hierarchical porosity consisting of macropores generated by strand deposition as well as an interconnected microporosity within the strands as result of the freeze-drying process. Cultivation of human mesenchymal stromal cells on the scaffolds, with and without adipogenic or osteogenic stimulation, revealed their cytocompatibility and potential applicability for adipose and bone tissue engineering.
authors.affiliation: Centre for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus and Faculty of Medicine of Technische Universität Dresden, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Lode
authors.forename: Michael
authors.initials: M
authors.lastname: Meyer
authors.forename: Sophie
authors.initials: S
authors.lastname: Brüggemeier
authors.forename: Birgit
authors.initials: B
authors.lastname: Paul
authors.forename: Hagen
authors.initials: H
authors.lastname: Baltzer
authors.forename: Michaela
authors.initials: M
authors.lastname: Schröpfer
authors.forename: Claudia
authors.initials: C
authors.lastname: Winkelmann
authors.forename: Frank
authors.initials: F
authors.lastname: Sonntag
authors.forename: Michael
authors.initials: M
authors.lastname: Gelinsky
mesh_terms: D050156:Adipogenesis / Q000502:physiology*; D001861:Bone Regeneration / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry*; D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D008422:Materials Testing; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology*; D066330:Printing, Three-Dimensional; D013499:Surface Properties; D013718:Tensile Strength; D054457:Tissue Scaffolds; D014783:Viscosity
chemical_list: D003094:Collagen