Advanced healing potential of simple natural hydrogel loaded with sildenafil in combating infectious wounds

Infected wounds are common clinical injuries that often complicated by inflammation and oxidative stress due to bacterial invasion. These wounds typically suffer from impaired vascularization, which delays healing and increases the risk of complications such as sepsis and chronic wounds. Therefore, developing an effective treatment for infected wounds is highly necessary. Egg white can promote cell regeneration and repair, while chitosan is effective in resisting bacterial invasion. Sildenafil is believed to have the potential to promote angiogenesis. Based on these properties, we have prepared a new type of hydrogel using egg white and chitosan as the framework, loaded with sildenafil (CEHS). The hydrogel combines the benefits of its components, exhibiting good biocompatibility and promoting the proliferation and migration of NIH 3T3 (3T3) cells and human umbilical vein endothelial cells (HUVEC), as well as the angiogenesis in HUVEC. It also exhibits significant antioxidant, anti-inflammatory, and antibacterial properties against <i>Escherichia coli (E. coli)</i> and <i>Staphylococcus aureus (S. aureus)</i>. Additionally, in a mouse model of infected wounds, the CEHS effectively promoted wound healing through its excellent antioxidant and anti-inflammatory properties, antibacterial activity, and pro-angiogenic effects. In summary, this simple-to-prepare, multifunctional natural hydrogel shows great promise for the treatment of infected wounds.