Self-Cross-Linked Oxidized Sodium Alginate/Gelatin/Halloysite Hydrogel as Injectable, Adhesive, Antibacterial Dressing for Hemostasis

Hemorrhage and infection of wounds are major causes of death; hence, the development of hemostasis materials with antibacterial properties is of significant importance. In this study, a composite hydrogel (OSA/Gel/HNTs) was designed through a one-step approach by using oxidized sodium alginate (OSA) and gelatin as a matrix with halloysite nanotubes (HNTs) as nanofillers in the presence of borax. The interactions among HNTs, OSA, and gelatin were analyzed by Fourier-transform infrared spectroscopy (FTIR) and microscopic morphology. By the synergistic action of Schiff base cross-linking, hydrogen bonding, and electrostatic attraction, the hydrogels showed good injectability, skin adhesion, and self-healing properties. HNTs effectively increased the degree of cross-linking of hydrogels, shortened the gelation time (∼202 s), enhanced the mechanical properties (∼332 kPa), and reduced the swelling. OSA/Gel/HNTs hydrogels showed good antibacterial activity against Staphylococcus aureus and Escherichia coli . In addition, the composite hydrogel showed good hemostatic properties by shortening the clotting time and decreasing the bleeding volume in a mouse liver hemorrhage model and a femoral artery injury model. Therefore, OSA/Gel/HNTs hydrogels have promising application prospects in hemostasis and wound healing areas.