Hydrogel-based scaffolds for tissue engineering

S. Joshi, S.R. Singh
Alabama State University,
United States

Keywords: hydrogel, scaffold, alginate, tissue engineering


Gels or hydrogels are described as the matrix of cross-linked polymers. Hydrogels are naturally a part of the body in the form of collagen, gelatin, mucous, tear films, cartilage, vitreous humor, cornea, and tendon. The high water content of the hydrogel scaffold mimics the properties of the soft tissue such as porosity, which helps in the diffusion of nutrients. Alginate is a component of the extracellular matrix (ECM) in the form of polysaccharide, and it is one of the biomaterials used in the preparation of hydrogel scaffolds. To protect cells, the alginate based matrix for immobilization of the cells was first described in 1990, and since then, numerous experiments have been attempted using alginate based scaffold for cell shielding and tissue engineering. This research represents a hydrogel scaffold designed to shield and grow the keratinocytes. Briefly, the hydrogel scaffold was prepared using keratinocytes mixed gently in 2 % sodium alginate dissolved in keratinocytes medium supplemented with growth supplement. The mixture was then gently transferred to a mold and gelation was proceeded in the presence of 2 % calcium chloride (CaCl2). Toxicity of sodium alginate and calcium chloride was assessed against keratinocytes using MTT assay. The hydrogel scaffold was stored in an incubator at 37˚C, 5 % CO2 and the viability of keratinocytes was imaged using fluorescence imaging. Three different concentrations of Na-alginate (0.5, 1 and 2 % w/v) and CaCl2 (0.5, 1 and 2 % w/v) were assessed for the toxicity, and over 90 % cell viability was observed for 72 h for all the samples. The fluorescence imaging from two different regions of the same scaffold not only confirms aliveness of keratinocytes but also cell replication as the number of keratinocytes is increased. Overall, the results and observation at this stage of the research represent that the alginate-based hydrogel scaffold holds the potential of being used in tissue engineering applications such as ECM mimicking, biosensors, etc.