Speaker
Description
Efficient vascularization is critical for ensuring adequate nutrient and oxygen transport as well as metabolic waste removal in engineered tissues. Conventional strategies often depend on angiogenesis from existing vasculature, inherently limiting construct size and functional complexity. Nonetheless, the generation of structurally stable and perfusable constructs remains a significant hurdle in tissue engineering. Among fabrication strategies, microfluidic-based techniques provide precise modulation over fiber geometry, dimensions, and surface chemistry.In this study, we employed a coaxial microfluidic-assisted wet spinning approach to fabricate compliant, vessel-like hydrogel fibers composed of alginate and tyramine-functionalized gelatin (Gela-Ph). This system harnessed the biocompatibility and bioactivity of gelatin alongside the rheological advantages of both core and shell alginate/Gela-Ph solutions to produce continuous fibers in a calcium chloride coagulation bath. Post-spinning, the fibers were further stabilized via a visible-light-triggered crosslinking process, wherein phenolic groups on Gela-Ph were covalently linked using riboflavin as the photoinitiator and persulfate as the electron donor.The resulting hydrogel vessels exhibited uniform morphology and remained free of polymer aggregation or channel occlusion under optimized flow and reagent conditions. By modulating inner and outer flow rates, vessel diameter and membrane thickness were finely tunable. Spectroscopic analyses (FTIR and NMR) verified the successful conjugation of tyramine to gelatin and its subsequent covalent crosslinking. The photo-crosslinking strategy conferred enhanced mechanical resilience, elasticity, and sustained cell viability within the fibers for up to 24 days. Perfusion assays demonstrated flow rates from 0.1 to 20 mL/min, replicating physiological conditions observed in native venous microvasculature.The integration of Gela-Ph with visible-light-mediated crosslinking within alginate-based hydrogel fibers presents a promising platform for vascular tissue engineering. The system offers mechanical flexibility, biocompatibility, and functional flow capacity, though further refinement is necessary to advance toward clinical applicability and therapeutic use.
