Horseradish peroxidase/catalase-mediated cell-laden alginate-based hydrogel tube production in two-phase coaxial flow of aqueous solutions for filament-like tissues fabrication.

We report a method for preparing cell-laden hydrogel tubes. This method uses a coaxial double-orifice spinneret, simpler than triple-orifice spinnerets which have been used for preparing similar constructs. The intended application was to create a template for preparing filament-like structures composed of two heterogeneous living cell layers. An aqueous solution containing an alginate derivative possessing phenolic hydroxyl moieties (Alg-Ph), catalase and horseradish peroxidase (HRP) was extruded into an ambient flow of H(2)O(2) aqueous solution. This operation enabled the Alg-Ph solution to be gellable through a HRP-catalyzed reaction, cross-linking the Ph moieties together. By altering flow rates of the Alg-Ph and H(2)O(2) solutions along with the concentrations of catalase and H(2)O(2), the diameter and membrane thickness of the hydrogel tubes were controllable between 250-550 µm and 70-140 µm, respectively. The viability of the HeLa cells enclosed in the hydrogel tubes with a diameter of 300 µm and a membrane thickness of 80 µm was 95.4%. Subsequently, the enclosed HeLa cells grew and filled the hollow core. A filament-like structure of HeLa cells covered with a layer of fibroblast 10T1/2 cells was obtained when confluency of fibroblast 10T1/2 cells was reached and the hydrogel matrix was degraded with alginate lyase.