Novel chitosan/hydroxypropyl methylcellulose/propylene glycol hydrogel containing lyophilized amniotic membrane particles for wound healing: Synthesis and optimization.

Chronic wounds pose challenges due to delayed healing and infection risks. Advanced dressings that provide moisture, support, and bioactivity are critical for regeneration. Hydrogels offer high water content and biocompatibility, while the human amniotic membrane (hAM) provides proteins and growth factors that enhance healing. However, hAM's fragility limits direct use. This study developed a hydrogel of chitosan, hydroxypropyl methylcellulose (HPMC), and propylene glycol (PG), incorporating lyophilized hAM particles to combine the hydrogel's physicochemical properties with hAM's bioactivity. Chitosan hydrogels crosslinked with β-glycerophosphate were optimized for gelation, swelling, degradation, FTIR, rheology, and strength. The optimized formulation exhibited controlled degradation and stability. Incorporating hAM (5% w/v) enabled sustained protein release without disrupting the network (FTIR). Characterization included FTIR and Bradford protein assays. Biological evaluations assessed cytotoxicity and antibacterial activity. The hydrogel showed rapid gelation (<10 min at 37 °C), high swelling (166.07 ± 41.03%), strength (110 ± 60 Pa), >85% L929 fibroblast viability, and inhibition of gram-positive and -negative bacteria. The self-healing AM-loaded hydrogel shows promising properties for wound dressings. Further in vivo and clinical studies are warranted.