Development of a bioinspired mat with chitosan functionality: Engineered scaffold for tissue regeneration

Tissue engineering and cellbased therapies are the two areas of regenerative medicine research that have received the greatest attention. It has been demonstrated that the choice of materials are critical success elements. Natural polymers are preferred by cells as binding scaffolds because they promote cellular adhesion, migration and proliferation. The goal of this work is to develop a biopolymerfunctionalized cell scaffold that can mimic the extracellular matrix. Chitosan is a natural polymer known for its antimicrobial effect. Chitosan nanoparticles (CSNPs) were manufactured by ionic gelation method. The morphologies of the NPs were evaluated by (Scanning Transmission Electron Microscopy) STEM.  CSNP diameter, zeta potential and polydispersity index (PDI) were measured by Nanoplus 3 Nanoparticle Size/ Zeta Potential Measurement Device). A biocompatible polymer, PCL, and a natural polymer, gelatin, were dissolved in hexafluoro isopropanol and the polymer suspension containing CSNPs was electrospun. Electrospinning was performed using a highvoltage power supply set to 14 kV, a collector distance of 12.5 cm, and a flow rate of 0.5 ml/hour. Fiber morphologies and diameters were determined by FESEM analysis. The attachment of keratinocyte cells onto the functionalized fiber mat was observed using SEM analysis and DAPI staining. The biocompatibility of the fiber mat was determined by XTT cytotoxicity tests after 72 hours of incubation with keratinocyte cells. The results demonstrated that CSNPs have spherical morphologies, with a mean diameter of 187 nm and a zeta potential of 35.75 mV. The electrospun bioinspired mat exhibited an average fiber diameter of 560 nm. Cell attachment and biocompatibility tests indicated that the CNNP functionalized mat could be considered as a biocompatible scaffold to facilitate cell growth and regeneration. The authors acknowledge the support of the REGENEU project (no:101079123) funded by Horizon Europe.