Fabrication and Characterization of Modified Silk Fibroin/Zinc-Based Metal-Organic Framework Composite Hydrogel Using Fenton Reaction for Medical Applications

Introduction and Objectives: Hydrogels, as three-dimensional hydrophilic scaffolds, play a crucial role in absorbing biological fluids and providing mechanical stability in the tissue regeneration process. This study aims to design and synthesize novel composite hydrogels based on thiol-modified silk fibroin and a zinc-containing bio-metal-organic framework (Zn-Bio MOF) with an adenine ligand to enhance mechanical and biological properties for tissue engineering applications.Materials and Methods: Pure silk fibroin was extracted and modified with thiol groups via L-cysteine conjugation. Fourier-transform infrared (FTIR) spectroscopy was conducted to confirm these modifications. The Zn-Bio MOF was synthesized through a hydrothermal process using zinc (II) ions and an adenine ligand. Three types of composite hydrogels were prepared: (1) hydrogel based on thiol-modified silk fibroin, (2) hydrogel based on thiol-modified silk fibroin crosslinked via the Fenton reaction, and (3) composite hydrogel containing Zn-Bio MOF at various concentrations. Material characterization was performed using scanning electron microscopy (SEM) and X-ray diffraction (XRD).Results: FTIR spectroscopy confirmed the reduction in peak intensities at 1650 cm⁻¹ and 3300 cm⁻¹ and the appearance of new peaks corresponding to S-S and S-H bonds. The average particle size of Zn-Bio MOF was 0.39 ± 0.12 nm, with a specific surface area of 1138.3 m²/g. Swelling and degradation analyses indicated that Zn-Bio MOF-containing hydrogels exhibited improved mechanical properties, including higher compressive modulus and toughness, approximately 30% weight loss over 72 hours, and controlled swelling behavior.Conclusion: The findings of this study suggest that Zn-Bio MOF composite hydrogels, due to their enhanced mechanical properties and controlled swelling behavior, hold significant potential for tissue engineering and biomedical applications.