| Abstract Scope |
Supplying nutrients to large engineered tissues remains a key challenge in biomedical device fabrication. We present a hybrid multiscale 3D printing strategy that seamlessly integrates perfusable microvessels into tissue models. Using a modified digital light processing (DLP) technique, we rapidly produce transparent base structures with recessed chambers. High-resolution two-photon stereolithography (TPS) is then used to directly print intricate microvascular networks within these chambers. This enables the creation of freestanding channels with diameters as small as 50 µm, lengths up to 15 mm, and complex features like branching and micropores (1–50 µm) for controlled diffusion. We thoroughly characterized printing parameters, surface interactions, fluid flow, and vessel permeability. The resulting system demonstrated high biocompatibility and stable performance in tissue models. By combining DLP and TPS, this method bridges macro- and microscale fabrication in a single device, offering a versatile platform for biomedical engineering, microfluidics, sensors, and next-generation microsystem design. |