3D Printing of Multiscale Scaffolds with Microtopography for Guiding Tissue Organization and Regeneration

Engineering biomaterial scaffolds with multiscale structures, integrating anatomically accurate macroscale architecture (millimeters to centimeters) with microtopographic features (sub-microns to tens of microns), is critical for guiding cellular organization and tissue regeneration. However, fabricating such multiscale scaffolds remains challenging due to the limitations of conventional manufacturing techniques and the trade-off between speed and resolution in current 3D printing methods. Here, we present a multiscale micro-continuous liquid interface production (M{micro}CLIP) technique that enables rapid, one-step 3D printing of centimeter-scale scaffolds with spatially tunable microtopography of various sizes and geometries in just a few minutes (up to 1 mm/min). To showcase the versatility of our technique, we printed a one-centimeter-long tubular scaffold with dual microtopographic patterns, i.e. 20 {micro}m axially aligned grooves on the internal surface and 15 {micro}m circumferentially aligned rings on the external surface. These scaffolds induced the simultaneous orientation of vascular endothelial cells along the axial grooves and vascular smooth muscle cells along the circumferential rings, mimicking the orthogonally aligned bilayer architecture of natural arteries. Moreover, the groove patterns significantly accelerated endothelial cell migration, potentially enhancing endothelialization in vascular implants. This approach provides a versatile tool for designing advanced scaffolds and medical devices that harness microtopography to guide tissue organization and enhance regeneration.