3D printing of heterogeneous microfibers with multi‐hollow structure via microfluidic spinning

Tissues with tubular structures play important roles in the human bodies, such as mass transport, nutrition exchange, and waste filtration. However, it remains a challenge to generate micro-scaffolds with well-defined luminal structure in biomedical field. In this study, we proposed a novel method to fabricate multi-component microfibers with multi-hollow structure via microfluidic spinning, which can subsequently be integrated with 3D printing for tissue-like block assembling. To achieve this goal, we fabricated a microchip using a 3D printed template with adjustable heights. Utilizing this microchip, we successfully generated the Calcium alginate microfibers with multi-components and defined hollow structures in a controllable manner. Then this microfluidic spinning method was integrated with a 3D mobile platform to assemble the microfibers into a grid-like 3D architecture. The resulted 3D scaffolds exhibited good organization and maintained the hollow structure of the fibers. Furthermore, we successfully developed a bronchus model utilizing this strategy by loading pulmonary bronchial epithelium cells and endothelial cells into microfibers with two hollow structures. The present strategy provides a potential platform to rebuild the lumen-like tissues using microfibers.