The Bioactivity of Janus-like CuO-Ag Nanoparticles on Antibiotic-Resistant Clinical Isolates of Klebsiella pneumoniae and their Mechanism of Action.

The current study aimed to research the bioactivity of Janus-like CuO-Ag nanoparticles (NPs) against clinical isolates of Klebsiella pneumoniae. The synthesis of CuO-Ag NPs was carried out by electric explosion of two twisted wires (EETW) method. The bioactivity of Janus-like CuO-Ag NPs was assessed by the determination of antibiofilm, antiadhesion, antibiotic sensitivity effect, and cytotoxicity on 3T3 cell line. The results indicate that the antibiofilm activity of these Janus-like CuO-Ag particles at subinhibitory concentrations was found to be between 2 and 10 times more potent than that of a mechanical mixture of CuO and Ag, separated Cu and Ag. Furthermore, the effective concentrations necessary for antiadhesion activity against K. pneumoniae were significantly lower for the Janus-like CuO-Ag particles, recorded at 2.0 and 10.0 µg/ml, in contrast to the control, which showed values of 7.3 ± 0.2% and 46.7 ± 0.4%, respectively (P < 0.05). Along with this, Janus-like CuO-Ag NPs increased the diameters of the antibiotic inhibition zones K. pneumoniae: for Imipenem from 5.0 ± 0.8 to 10.0 ± 1.0 mm, Gentamicin from 15.0 ± 2.0 to 20 ± 2.0 mm, and Amikacin from 13.0 ± 2.0 to 21 ± 2.0 mm (p < 0.05). We showed that ROS generation and Ag + release made only a small contribution to the bioactivity of CuO-Ag NPs. Notably, the generation of copper ions were increased from 7,5 μg/L ± 0.1% to 25 ± 1% μg/L within 24 h of exposure NPs (P < 0.05). At the same time, the cytotoxicity test confirmed favorable safety profiles of the synthesized NPs.