Production of luffa cylindrica reinforced silk fibroin-chitosan hydrogel scaffolds for cartilage tissue defects

Current therapies for the treatment of cartilage defects are limited due to the low self-healing capacity of cartilage. In recent years, tissue engineering has been proposed as a promising approach for cartilage regeneration. In this study, silk fibroin-chitosan hydrogels reinforced with Luffa cylindrica were prepared for cartilage tissue defects. Biocompatible, biodegradable silk fibroin and chitosan polymers were cross-linked with genipin which is a natural and nontoxic crosslinking agent. In order to improve the mechanical properties of hydrogel scaffolds, Luffa cylindrica was used as the reinforcement. Scaffolds were prepared by mixing chitosan and silk fibroin solutions at a volume of 1: 1 followed by adding Luffa cylindrica and freeze-drying. Then, the freeze-dried scaffolds were crosslinked with genipin at different concentrations. The influence of genipin concentration and addition of the Luffa cylindrica on the scaffold properties were evaluated. The morphologies and chemical structures of the scaffolds were characterized by scanning electron microscope (SEM) and Fourier-transformed infrared spectroscopy (FTIR), respectively. The swelling ratio test of the scaffolds was carried out in phosphate buffered saline (PBS) solution. Furthermore, the viscoelastic and mechanical properties of the scaffolds were examined by dynamic mechanic analysis (DMA) and compression test. As a result of the study, among the Luffa cylindrica reinforced composite tissue scaffolds, L-CSG3 showed similar properities with the human cartilage tissue in terms of compressive modulus and tan delta values.