Eco synthesized chitosan/zinc oxide nanocomposites as the next generation of nano-delivery for antibacterial, antioxidant, antidiabetic potential, and chronic wound repair.

The present research work aimed at synthesizing chitosan-coated Zinc oxide nanocomposites (NS-CS/ZnONCs) by a bio-inspired method using an aqueous extract of Nigella sativa (NS) seeds and employing a quality-by-design approach (Box-Behnken design). The biosynthesized NS-CS/ZnONCs were physicochemically characterized and subjected to their in-vitro and in-vivo therapeutic potential. The zeta potential value of -11.2 mV and -12.6 mV indicated the stability of NS-mediated synthesized zinc oxide nanoparticles (NS-ZnONPs) and NS-CS/ZnONCs, respectively. The particle size of NS-ZnONPs and NS-CS/ZnONCs were 288.1 nm and 130.2 nm, respectively, with PDI of 0.198 and 0.158. NS-ZnONPs and NS-CS/ZnONCs showed superior radical scavenging abilities, excellent α-amylase, and α-glucosidase inhibitory activities. Also, NS-ZnONPs and NS-CS/ZnONCs demonstrated effective antibacterial activity against selected pathogens. Furthermore, NS-ZnONPs and NS-CS/ZnONCs demonstrated significant (p < 0.001) wound closure with 93.00 ± 0.43 % and 95.67 ± 0.43 % on the 15 day of treatment at the dose of 14 mg/wound, compared to 93.42 ± 0.58 % of standard. Collagen turnover was represented by hydroxyproline, which was shown to be significantly (p < 0.001) higher in the NS-ZnONPs (60.70 ± 1.44 mg/g of tissue) and NS-CS/ZnONCs (66.10 ± 1.23 mg/g of tissue) treatment groups than in the control group (47.7 ± 0.81 mg/g of tissue). Thus the NS-ZnONPs and NS-CS/ZnONCs could effectively develop promising drugs to inhibit pathogens and chronic tissue repair.