Highly Flexible Methyl Cellulose/Gelatin Hydrogels for Potential Cartilage Tissue Engineering Applications

Cartilage damage resulting from trauma demonstrates a poor capacity for repair due to its avascular nature. Cartilage tissue engineering offers a unique therapeutic option for cartilage recovery. In this study, methylcellulose (MC)/gelatin (GEL) hydrogels (MC10G20, MC12.5G20, MC15G20, and MC17.5G20) were developed to assess and compare their chemical, mechanical, and biological characteristics for cartilage repair. First, the interaction between MC and GEL after blending and subsequent crosslinking with EDC/NHS was confirmed by using FTIR. Mechanical tests under compression test revealed that hydrogels' resistance to both elastic and plastic deformation increased with higher wt.% of MC. The % strain of the hydrogels doubled with the addition of MC, likely due to abundant hydrogen bonding between polymeric chains. Furthermore, the compressive modulus of MC/GEL hydrogels was approximately 0.2 MPa, closely matching modulus of human cartilage tissue. Similarly, the % water retention capacity of the hydrogels increased over the 7 days as the MC content increased. Additionally, SEM images showed that the incorporation of MC to GEL introduced porosity with the diameters ranging from 10 to 50 μm, similar to the size of pores in native cartilage. In vitro cell culture studies confirmed the biocompatibility of MC/GEL hydrogels. Fluorescence staining showed a 2.5-fold increase in F-actin staining following the incorporation of MC into the hydrogels. Overall, this study highlights the potential of MC/GEL hydrogels for cartilage tissue engineering, however, further research is required to assess its full potential.