Evaluation of the Antibacterial Properties of Iron Oxide, Polyethylene Glycol, and Gentamicin Conjugated Nanoparticles against Some Multidrug-Resistant Bacteria

Antibacterial resistance is observed as a public health issue around the world. Every day, new resistance mechanisms appear and spread over the world. For that reason, it is imperative to improve the treatment schemes that have been developed to treat infections caused by wound infections, for instance, Staphylococcus epidermidis (S. epidermidis), Proteus mirabilis (P. mirabilis), and Acinetobacter baumannii (A. baumannii). In this case, we proposed a method that involves mixing the Gentamicin (Gen) with iron oxide nanoparticles (Fe(3)O(4) NPs) and a polymer (polyethylene glycol (PEG)) with Fe(3)O(4) NPs. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), scanning electron microscope (SEM), and transmission electron microscope (TEM) were used to characterize Fe(3)O(4) NPs. Zeta potential and dynamic light scattering (DLS) were also assessed. The antibacterial activity of Fe(3)O(4) NPs, Fe(3)O(4) NPs+PEG, Fe(3)O(4) NPs+Gen, and Fe(3)O(4) NPs+PEG+Gen composites was investigated. The results showed a significant improvement in the antibacterial activity of nanoparticles against bacterial isolates, especially for the Fe(3)O(4) NPs+PEG+Gen as the diameter of the inhibition zone reached 26.33 ± 0.57 mm for A. baumannii, 25.66 ± 0.57 mm for P. mirabilis, and 23.66 ± 0.57 mm for S. epidermidis. The Fe(3)O(4) NPs, Fe(3)O(4) NPs+PEG, Fe(3)O(4)+Gen, and Fe(3)O(4)+PEG+Gen also showed effectiveness against the biofilm produced by these isolated bacteria. The minimum inhibitory concentration (MIC) of Fe(3)O(4) NPs for S. epidermidis was 25 µg mL(−1) and for P. mirabilis and A. baumannii was 50 µg mL(−1). The findings suggest that the prepared nanoparticles could be potential therapeutic options for treating wound infections caused by S. epidermidis, P. mirabilis, and A. baumannii.