3D Printed Methacrylate-modified Chitosan / Methylcellulose Blend Hydrogel Scaffolds for Body Tissue Regeneration

In tissue engineering, 3D scaffolds serve as temporary extracellular matrices to support cell growth, proliferation and differentiation. But a scaffold made from a single biopolymer has limited functionalities. Scaffolds can be tailored to possess desired properties by using two or more biopolymers. UV-crosslinkable methacrylate-modified chitosan (CSMA) is based on cell-compatible chitosan and methylcellulose (MC) is a non-toxic polymer. Blends of CSMA and MC are attractive materials for tissue engineering scaffolds with good biocompatibility and mechanical properties. 3D printing is powerful and can fabricate customized scaffolds according to clinical needs. In this study, polymer blends of CSMA and MC were prepared for 3D printing of hydrogel scaffolds. Rheological properties of blend hydrogel inks were studied, and optimized inks were used for 3D printing. The morphology and structure of 3D printed blend hydrogel scaffolds were examined. Also, mechanical properties, thermal stability, water absorption, etc. of 3D hydrogel scaffolds were investigated. It was found that the addition of MC to CSMA provided required viscoelastic behavior and hence good printability, which allowed 3D printing of multi-layered porous structures without collapsing and ensured structural integrity of printed scaffolds. In addition, the blended networks of CSMA and MC resulted in good mechanical strength of scaffolds. Biological tests revealed good biocompatibility of the blend hydrogel scaffolds.