Fabrication and evaluation of pectin-gelatin skin tissue engineering scaffolds containing amoxicillin trihydrate-loaded UiO-66-NH2 nanoparticles

In this study, a novel nanocomposite scaffold comprising pectin, gelatin, and amoxicillin trihydrate-loaded UiO-66-NH 2 metal-organic frameworks (UiO-66-NH 2 @AMX) was fabricated for skin tissue engineering applications. UiO-66-NH 2 nanoparticles were synthesized hydrothermally and subsequently loaded with amoxicillin trihydrate. Finally, UiO-66-NH 2 @AMX nanoparticles were incorporated into pectin-gelatin scaffolds using the freeze-drying method. FE-SEM imaging confirmed the octahedral morphology of the nanoparticles before and after drug loading. FTIR analysis demonstrated successful drug incorporation via non-covalent interactions. DLS and zeta potential measurements showed that UiO-66-NH 2 nanoparticles had a mean size of 218.5 ± 14 nm and a surface charge of +44.1 ± 2.7 mV. After drug loading, the size slightly increased to 248.8 ± 19 nm, and the surface charge decreased to +32.6 ± 2.5 mV, while maintaining colloidal stability. All of the scaffolds showed porous structures with interconnected pores in SEM imaging. The incorporation of UiO-66-NH 2 @AMX nanoparticles into the pectin-gelatin scaffolds up to 3 % (w/w) increased the tensile strength and Young's modulus of the scaffolds 37.6 % and 56.7 %, respectively. Antibacterial activity was evaluated by CFU assay, where UiO-66-NH 2 @AMX containing scaffolds revealed significant bacterial reduction against E. coli and S. aureus colonies. MTT, cell adhesion, and cell scratch assays conducted on L929 fibroblasts. All of the scaffolds demonstrated >85 % cell viability after 3 days of culture. Furthermore, scaffolds with 3 % (w/w) UiO-66-NH 2 @AMX enhanced cell adhesion and increased migration rate in scratch closure assay. Overall, the results indicate that the novel nanocomposite scaffolds are promising candidates for skin tissue engineering and wound healing applications.