Biosynthesis of a Polyhydroxybutyrate/Ziziphus spina-christi–ZnONPs for Smart Wound Dressing: A Multi-Functional Biomaterial with controlled ZnONPs Release and Potent Bioactive Properties

Despite considerable advancements in medicine recently, successfully managing infected wounds remains a challenge. Traditional wound dressings usually do not possess the capability to achieve controlled ZnONPs release, biocompatibility, antioxidant properties, antidiabetic effects, non-toxicity, and antimicrobial at the same time. This study focus on the biosynthesis of polyhydroxybutyrate (PHB) and Ziziphus spina-christi-ZnONPs and combining them with chitosan (CS) and polyvinyl alcohol (PVA) to overcome limitations and develop novel, multifunctional wound dressing. PHB production was obtained by isolated bacteria and optimized using a Box-Behnken Design (BBD). The optimized medium yielded 3.5 g/L of PHB, closely aligning with the predicted value of 3.7 g/L. Additionally, Ziziphus spina-christi-ZnONPs were produced utilizing a Ziziphus spina-christi extract and analyzed through UV-Vis spectra, FTIR, XRD, and TEM. The fabricated PHB/CS/PVA/ZnONPs nanocomposite exhibited significant high swelling degree, and degradation ability (66 ± 3.3%). According to the preliminary in vitro findings, PHB/CS/PVA/ZnONPs have high antioxidant (69.2%), anti-inflammatory (⁓90% inhibition of protein denaturation), and antidiabetic (55–60%) characteristics. Biocompatibility assays revealed no adverse effects on blood coagulation or hemolysis. Moreover, the innovative PHB/CS/PVA/ZnONPs improved bioactive properties, including superior broad-spectrum antimicrobial efficacy (⁓ 99.9%) against wounds and diabetic foot ulcer strains (S. aureus, E. coli, P. aeruginosa, and K. pneumoniae). Furthermore, MTT assays confirmed enhanced cell viability in HEK-293 normal cells for PHB/CS/PVA/ZnONPs containing 0.1 mg/ml of Ziziphus spina-christi-ZnONPs. Release kinetics followed the Korsmeyer-Peppas model, indicating the bionanomaterial’s potential as a controlled ZnONPs release. These multifunctional attributes validate the PHB/CS/PVA/ZnONPs nanocomposite as a promising and biocompatible candidate for advanced wound dressing applications.