A novel dual-adhesive and bioactive hydrogel activated by bioglass for wound healing

Dual adhesiveness to tissue and implant biomaterials and bioactivity to stimulate tissue regeneration are interesting properties for developing new generations of tissue-repairing hydrogels with potential new clinical applications. In this study, we developed a unique bioglass (BG)/oxidized sodium alginate (OSA) composite hydrogel with adipic acid dihydrazide (ADH)-modified γ-polyglutamic acid (γ-PGA) as the cross-linking agent, in which the BG plays a multifunctional role to endow the hydrogel‍ with both dual-adhesive and bioactive properties. On one hand, the BG could improve the tissue-bonding strength by providing an alkaline microenvironment to stimulate the bond formation between OSA and the amino groups on the surrounding tissues. On the other hand, BG endows the hydrogel‍ with adhesiveness to implantable materials by releasing Ca ions, which might chelate with the carboxyl groups of the hydrogel‍ matrix. In addition, the composite hydrogel‍ showed excellent bioactivity to promote vascularization and accelerate tissue regeneration. This study demonstrates that a multifunctional hydrogel‍ can be designed by utilizing the multifunctional ions released from silicate BG, and the BG/OSA hydrogel shows good potential as an adhesive and bioactive material for wound-healing applications. An inorganic material known as bioglass can help water-filled hydrogel polymers adhere to injuries and implants that require moist, protective environments. Composed of silica glass infused with calcium, silicate and phosphate ions, bioglass can help regenerate substances such as bone tissue while resisting rejection by the body’s immune system. Jiang Chang and colleagues from the Chinese Academy of Sciences in Shanghai now report that the ions in bioglass can accelerate the formation of bonds between tissue and hydrogels based on alginate, a polysaccharide extracted from seaweed. The team’s studies on live mice demonstrated that the enhanced adhesiveness of the new bioglass hydrogel led to better wound healing compared to stitching or conventional hydrogels. Calcium ion release was identified as a primary factor in helping the new composite stick to implants made from materials including silicone and titanium. The dual-adhesive and bioactive hydrogel ‍is designed and prepared for wound closure and wound healing by incorporation of bioglass into oxidized sodium alginate (OSA) hydrogel system, in which the multifunctional ions released from bioglass play a key role for the dual-adhessiveness to both tissues and implantable materials and bioactivity in enhancing angiogenesis during wound healing.