Fabrication of novel composite materials by impregnating ZnO particles into bacterial cellulose nanofibers for antimicrobial applications

Abstract Composite materials containing zinc oxide (ZnO) particles have excellent antimicrobial properties and are non-toxic. ZnO particles were synthesized using a simple hydrothermal method employing glucose as a green reducing agent. This work aims to improve the synergistic effects of bacterial cellulose (BC) composites with ZnO particles (BC@ZnO composite). BC is produced by Gluconacetobacter xylinus using agricultural wastes as a substrate. ZnO particles were directly distributed on the surfaces of BC, which is a carrier with the capability to transport and deliver active ingredients. The morphological and structural characteristics were evaluated by field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy. ZnO has a unique star-like structure with a diameter of about 1.3 μm and is composed of small flakes with a thickness of about 29 nm. ZnO was uniformly embedded throughout the BC matrix. X-ray diffraction confirmed the structural identity of ZnO, consistent with the hexagonal wurtzite structure, and revealed pure cellulose crystals with altered crystallinity peaks. The antimicrobial activity of composite materials against pathogenic Staphylococcus aureus and Klebsiella pneumoniae demonstrated significant inhibition against both bacteria. These results indicate that the synthesized BC@ZnO composite materials are promising for antimicrobial applications in various biomedical fields.