Fabrication of Biodegradable Hydrogel Nano/microfiber and its Biomedical Applications

Abstract

In this research, several strategies are described to design artificial extracellular matrices (ECMs) for three-dimensional (3D) cell culture that mimics the in vivo-like environment of cells. The ECMs of animal tissue mainly consist of structural proteins such as collagen and sulfated/non-sulfated glycosaminoglycans (GAGs) (e.g., heparin and hyaluronic acid). The imitation of morphological cues of collagen fibers has been studied by electrospinning, which is a technique for nano/microfiber fabrication. At the same time, the GAGs exist in soluble form or bound form in ECMs, and sulfated polysaccharides or GAGs themselves have been incorporated with electrospun fibers to imitate ECMs. Conventionally, emulating the shape of collagen fibers was easily accomplished through the electrospinning of hydrophobic/hydrophilic polymers. However, simulating the actual state of collagen fibers, where GAGs are tethered and hydrated (a state where a significant amount of water is absorbed), proved to be challenging. Herein, the previous studies are merged to develop hydrogel fibers as artificial ECMs. One is the direct sulfation of electrospun fibers which are made from polyvinyl alcohol (PVA) and gelatin. The other is the incorporation of hyaluronic acid into electrospun fibers to control swelling behavior and water absorption capacity. In summary, various types of hydrogel nano/microfibers were fabricated, and quantitative and qualitative control of their physical and chemical characteristics was studied (e.g., swelling ratio, fiber diameter, and degree of sulfation). These nano/microfibers are potentially helpful in understanding the relation of fibrous matrices and cells and also can give inspiration to develop biomaterials for the next generations.