Omnidirectional 3D Printing of Anisotropic Nanofibrous Peptide Hydrogels

Anisotropic biological tissues contain hierarchical complexity from the nano to macro length scales. While novel fabrication strategies have advanced the creation of biomimetic architectures, most rely on biologically derived polymers that possess inherent batch-to-batch variability. Here, we fabricate omnidirectional anisotropic nanofibrous hydrogels using synthetic, self-assembling MultiDomain Peptides (MDPs). Using support bath-assisted extrusion 3D printing, MDP hydrogels are created with control over nanometer-scale fibrous alignment, ~150 {micro}m-scale print resolution, and centimeter-scale 3D architecture. Further, scaffold anisotropy is tuned by adjusting the ionic strength of the support bath, allowing fiber alignment to be decoupled from extrusion shear force and the ink used. Applying these hydrogels to in vitro tissue engineering, fabricated anisotropic hydrogels are shown to guide the alignment of multiple cell types within complex 3D prints. Furthermore, the gels are demonstrated to support the growth of human embryonic stem cell-derived cardiomyocytes into functional tissue. Collectively, this work introduces a platform for engineering anisotropic peptide hydrogels with hierarchical complexity, offering broad potential for bottom-up fabrication of functional human tissues in vitro.