A Versatile Method to Create Perfusable, Capillary‐Scale Channels in Cell‐Laden Hydrogels Using Melt Electrowriting

A major obstacle toward creating human-scale artificial tissue models is supplying encapsulated cells with oxygen and other nutrients throughout the construct. In particular, channels in hydrogels that match resolution density of smallest blood capillaries (≤10 µm) remains highly challenging. Here, a novel method demonstrated where polycaprolactone fibers printed using melt-electrowriting are cell-laden then physically removed to produce hollow, perfusable channels. This technique produces range channel diameters (10–41 circular cross-sections representing various crosslinking mechanisms. The can be formed as interconnected grids, hierarchically branched patterns, or stacked layers ≈200 µm spacing, thus matching average capillary human body. Alternatively, selective removal from melt electrowriting grid generate within reinforcing fiber network. performed presence cells, fibroblasts exhibiting gelatin methacryloyl showing no detectable cytotoxic effects. promising approach for very small hydrogel matrices, potential applications including vitro microfluidics.