Fabrication and Cell Culture Applications of Core-Shell Hydrogel Fibers Composed of Chitosan/DNA Interfacial Polyelectrolyte Complexation and Calcium Alginate: Straight and Beaded Core Variations

Abstract

Core-shell hydrogel fibers are widely used in cell culture applications. A simple and rapid method is presented for fabricating core-shell hydrogel fibers, consisting of straight or beaded core fibers, for cell culture applications. The core fibers are prepared using interfacial polyelectrolyte complexation (IPC) with chitosan and DNA. Briefly, two droplets of chitosan and DNA are brought in contact to form an IPC film, which is dragged to prepare an IPC fiber. The incubation time and DNA concentration are adjusted to prepare straight and beaded IPC fibers. The fibers with Ca2+ are immersed in an alginate solution to form calcium alginate shell hydrogels around the core IPC fibers. To the best of the knowledge, this is the first report of core-shell hydrogel fibers with IPC fiber cores. To demonstrate cell culture, straight hydrogel fibers are applied to fabricate hepatic models consisting of HepG2 and 3T3 fibroblasts, and vascular models consisting of human umbilical vein endothelial cells and 3T3 fibroblasts. To evaluate the effect of co-culture, albumin secretion, and angiogenesis are evaluated. Beaded hydrogel fibers are used to fabricate many size-controlled spheroids for fiber and cloning applications. This method can be widely applied in tissue engineering and cell analysis.