Injectable multifunctional hydrogel based on carboxymethylcellulose/polyacrylamide/polydopamine containing vitamin C and curcumin promoted full-thickness burn regeneration

Burn injuries are a major global problem, with a high risk of infection and mortality. This study aimed to develop an injectable hydrogel for wound dressings, composed of sodium carboxymethylcellulose/polyacrylamide/polydopamine containing vitamin C (CMC/PAAm/PDA VitC) for its antioxidant and antibacterial properties. Simultaneously, silk fibroin/alginate nanoparticles (SF/SANPs) loaded with curcumin (SF/SANPs CUR) were incorporated into the hydrogel to enhance wound regeneration and reduce bacterial infection. The hydrogels were fully characterized and tested in vitro and in preclinical rat models for biocompatibility, drug release, and wound healing efficacy. Results showed stable rheological properties, appropriate swelling and degradation ratios, gelation time, porosity, and free radical scavenging capacity. Biocompatibility was confirmed through MTT, lactate dehydrogenase, and apoptosis evaluations. Hydrogels containing curcumin demonstrated antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). In the preclinical study, hydrogels containing both drugs showed superior support for full-thickness burn regeneration, with improved wound closure, re-epithelialization, and collagen expression. The hydrogels also showed neovascularization and anti-inflammatory effects, as confirmed by CD31 and TNF-α markers. In conclusion, these dual drug-delivery hydrogels showed significant potential as wound dressings for full-thickness wounds.