A hybrid scaffold of modified human amniotic membrane with gelatine/dendrimer-protected silver nanoparticles for skin wound healing applications

Abstract

The human amniotic membrane (hAM) is a biological material widely utilized to mimic the extracellular matrix in damaged skin. Despite its potential, clinical applications of hAM have been hindered by its poor mechanical properties. Furthermore, cryopreservation process used to store hAM could compromise its inherent bactericidal properties. This study explores an innovative approach by combining hAM with 2, 4, 6 and 8% w/v of gelatine (Gel) and incorporating 100, 500 and 1000 μL of poly(propylene imine) (PPI) dendrimer-protected silver nanoparticles (AgNPs) to create antibacterial-bolstered scaffolds using freeze-drying technique. Based on results, hAM/Gel2/S500 scaffold was identified as optimal specimen. It exhibited favorable properties, including an ultimate tensile strength of 16 kPa, an elastic modulus of 26.66 kPa, an elongation at break of 59.60%, an average pore size of 490 μm and a porosity of 52.93%. In vitro degradation indicated that degradation rate of the scaffold was 30% lower on the 1st day and 20% higher on the 21st day compared to commercial ChitoHeal dressing. It also demonstrated higher water absorbance of 100 and 139% at 1 and 48 hours, respectively, compared to ChitoHeal dressing. Additionally, uniform distribution of AgNPs throughout the scaffold and their release from 2.30 μg mL⁻¹ on the 1st day to 10.40 μg mL⁻¹ by the 3rd day, resulted in an elevated inhibition zone against S. aureus and E. coli. Finally, all antibacterial-bolstered scaffolds exhibited 85–89% cell viability after 24 hours and 80–83% after 72 hours. Consequently, hAM/Gel2/S500 scaffold showed promising results for application in wound healing.