Nanocomposites based on doped ZnO nanoparticles for antibacterial applications

Drug-resistant bacteria have become a worldwide health issue, and metal oxide nanoparticles could represent a viable alternative to pharmaceuticals for the treatment and prevention of bacterial infections. In this work, cerium (Ce), neodymium (Nd), samarium (Sm) and erbium (Er) doped ZnO nanoparticles were developed to fabricate 3D-printed composite scaffolds for bactericidal applications. The nanoparticles were prepared by a combustion-assisted method at low temperatures. The hexagonal wurtzite structure of ZnO was confirmed by X-ray diffraction (XRD), and the average crystallite size was similar to 10 nm. The bioactivity of these nanoparticles was evaluated by culturing them with Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The resulting bacterial kinetic growth curves showed superior antimicrobial activity against S. aureus, killing almost 92% of the bacteria, and intermediate activity against E. coil. The antibacterial activity of the scaffolds was studied to assess their potential for biomedical applications. The bacterial kinetic growth results were utilized as data in an artificial neural network (ANN), which resulted in a model capable of forecasting bacterial growth with high precision (90%).