Gelatin methacrylate/poly(2-ethyl-2-oxazoline) porous hydrogel loaded with kartogenin drug as a biocompatible scaffold for cartilage tissue regeneration

Gelatin methacrylate (GelMA) is a biocompatible, and biodegradable macromolecule developed from a natural polymer, gelatin, via covalent bonding with methacrylic groups. In this research, GelMA/poly(2-ethyl-2-oxazoline) (PEtOx) hydrogel loaded with Kartogenin (KGN) drug was developed with the aim to regenerate the extracellular matrix of cartilage. The morphology, swelling ratio, degree of hydrophilicity, biodegradability, elastic modulus, blood compatibility, drug release and cytotoxicity were assessed. The hydrogel was found to be hydrophilic, highly porous and biodegradable, with 92 % porosity and ∼ 43 % weight loss within 14 days. Mechanical testing revealed that the elastic modulus of GelMA (20 wt%)/PEtOx (45 wt%) was close to that of cartilage. Good blood compatibility and sustained drug release in the damaged cartilage tissue environment were also detected. According to flow cytometry and MTT tests, due to the presence of KGN, up to 75 % of the cells can survive and easily adhere to the developed scaffold. The results confirm the ability of GelMA/PEtOx hydrogel containing KGN to increase cell adhesion by preserving cell population combined with minimal cytotoxicity, which may be advantageous for use in cartilage regeneration following in-vivo implantation.