Development and Characterization of a Sustainable Pectin-Based Zeolite–Zno Hybrid Nanocomposite for Antibacterial Biomedical Applications

Abstract

A novel nanocomposite comprising pectin, zeolite, and zinc oxide (ZnO) nanoparticles (NPs) was hypothesised to enhance antibacterial activity through synergistic effects. Consequently, the material was investigated as a green antibacterial agent for biomedical applications. Pectin was extracted from green apples using ethanol precipitation and dried at 50°C. The nanocomposite was prepared by mixing 1% (w/v) pectin, 2% (w/v) zeolite, and 0.5% (w/v) ZnO nanoparticles in water, followed by stirring for 2 hours at room temperature. For antibacterial testing, 100 µL of a 10^6 CFU/mL bacterial suspension was spread on Mueller-Hinton agar. Composite discs (6 mm diameter, 20 mg) were placed on the plates. After 24 hours of incubation at 37°C, inhibition zones were measured. Minimum inhibitory concentrations were determined by broth microdilution (10–200 µg/mL) in 96-well plates. FTIR analysis confirmed the presence of functional group interactions within the materials. The pectin-zeolite-ZnO nanocomposite had strong antibacterial activity against both bacteria. For Staphylococcus aureus, the nanocomposite produced an inhibition zone of 18 ± 0.5 mm and for Escherichia coli, 16 ± 0.6 mm. These values were significantly greater than those observed for the pectin (9.3 ± 0.3 mm), zeolite (10.1 ± 0.4 mm), or ZnO nanoparticles alone (13 ± 0.5 mm). The minimum inhibitory concentration (MIC) for the nanocomposite was 40 µg/mL against S. aureus and 50 µg/mL against E. coli. This increase in antibacterial efficacy results from the synergy among zeolite, pectin, and ZnO nanoparticles, which enhances bacterial cell disruption and inhibition. The developed nanocomposite is a promising antibacterial agent. Its strong antibacterial activity suggests potential use in biomedical applications such as wound dressings, implant coatings, or antibacterial surfaces, where effective inhibition of bacterial growth is essential. These results highlight the nanocomposite's translational potential for preventing infections and supporting the development of safe biomedical devices.