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.

Unravelling hierarchical patterning of biomaterial inks with 3D microfluidic-assisted spinning: a paradigm shift in bioprinting technologies

“…Recently, Utagawa and others developed a rapid approach to generate a coreshell fibre, prepared from interfacial polyelectrolyte complexation (IPC), chitosan, DNA as core and Ca-alginate serving as shell (Figure 2A). The authors showed that the fibre shape can be changed by adjusting the concentration of DNA, providing an adequate environment for HepG2, 3T3, HUVECs, and 3T3 cells co-culturing (Utagawa et al, 2023).…”

“…FIGURE 2Different approaches in microfluidic 3D bioprinting: (A) Spun core-shell hydrogel fibre composed of chitosan/DNA IPC and the effect of Ca 2+ presence in chitosan or DNA on fibre length. Adopted with permission from(Utagawa et al, 2023). Hydrogel fibres with different diameter, microfluidic printhead to fabricate multiple material core extrusion for single-layer, multi-layer and hydrogel bundle printing with gradual color transition, Multilayered hydrogel bundles with variable core material fibres.…”