Ag-Doped and Antibiotic-Loaded Hexagonal Boron Nitride Nanoparticles as Promising Carriers to Fight Different Pathogens

Abstract

Utilization of antibacterial components-conjugated nanoparticles (NPs) is emerging as an attractive strategy for combating various pathogens. Herein, we demonstrate that Ag/BN NPs and antibiotic-loaded BN and Ag/BN nanoconjugates are promising carriers to fight bacterial and fungal infections. Extensive biological tests included two types of Gram-positive methicillin-resistant <i>Staphylococcus aureus</i> strains (B8469 and MW2), two types of Gram-negative <i>Pseudomonas aeruginosa</i> strains (ATCC27853 and B1307/17), and 47 types of <i>Escherichia coli</i> strains (including 41 multidrug-resistant ones), as well as five types of fungal cultures: <i>Candida albicans</i> (candidiasis-thrush) ATCC90028 and ATCC24433, <i>Candida parapsilosis</i> ATCC90018, <i>Candida auris</i> CBS109113, and <i>Neurospora crassa</i> <i>wt.</i> We have demonstrated that, even within a single genus <i>Escherichia</i>, there are many hospital <i>E. coli</i> strains with multi-drug resistance to different antibiotics. Gentamicin-loaded BN NPs have high bactericidal activity against <i>S. aureu</i><i>s</i>, <i>P. aeruginosa</i>, and 38 types of the <i>E. coli</i> strains. For the rest of the tested <i>E. coli</i> strains, the Ag nanoparticle-containing nanohybrids have shown superior bactericidal efficiency. The Ag/BN nanohybrids and amphotericin B-loaded BN and Ag/BN NPs also reveal high fungicidal activity against <i>C. albicans</i>, <i>C. auris</i>, <i>C. parapsilosis</i>, and <i>N. crassa</i> cells. In addition, based on the density functional theory calculations, the nature of antibiotic-nanoparticle interaction, the sorption capacity of the BN and Ag/BN nanohybrids for gentamicin and amphotericin B, and the most energetically favorable positions of the drug molecules relative to the carrier surface, which lead to lowest binding energies, have been determined. The obtained results clearly show high therapeutic potential of the antibiotic-loaded Ag/BN nanocarriers providing a broad bactericidal and fungicidal protection against all of the studied pathogens.