Three-dimensional extrusion bioprinting of single- and double-network hydrogels containing dynamic covalent crosslinks.

Autor: Wang LL; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, 19104., Highley CB; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, 19104., Yeh YC; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, 19104., Galarraga JH; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, 19104., Uman S; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, 19104., Burdick JA; Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, 19104.
Jazyk: angličtina
Zdroj: Journal of biomedical materials research. Part A [J Biomed Mater Res A] 2018 Apr; Vol. 106 (4), pp. 865-875. Date of Electronic Publication: 2018 Jan 23.
DOI: 10.1002/jbm.a.36323
Abstrakt: The fabrication of three-dimensional (3D) scaffolds is indispensable to tissue engineering and 3D printing is emerging as an important approach towards this. Hydrogels are often used as inks in extrusion-based 3D printing, including with encapsulated cells; however, numerous challenging requirements exist, including appropriate viscosity, the ability to stabilize after extrusion, and cytocompatibility. Here, we present a shear-thinning and self-healing hydrogel crosslinked through dynamic covalent chemistry for 3D bioprinting. Specifically, hyaluronic acid was modified with either hydrazide or aldehyde groups and mixed to form hydrogels containing a dynamic hydrazone bond. Due to their shear-thinning and self-healing properties, the hydrogels could be extruded for 3D printing of structures with high shape fidelity, stability to relaxation, and cytocompatibility with encapsulated fibroblasts (>80% viability). Forces for extrusion and filament sizes were dependent on parameters such as material concentration and needle gauge. To increase scaffold functionality, a second photocrosslinkable interpenetrating network was included that was used for orthogonal photostiffening and photopatterning through a thiol-ene reaction. Photostiffening increased the scaffold's modulus (∼300%) while significantly decreasing erosion (∼70%), whereas photopatterning allowed for spatial modification of scaffolds with dyes. Overall, this work introduces a simple approach to both fabricate and modify 3D printed scaffolds. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 865-875, 2018.
(© 2018 Wiley Periodicals, Inc.)
Databáze: MEDLINE
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