title: Potent antibacterial nanoparticles for pathogenic bacteria.
abstract: Antibiotic-resistant bacteria have emerged because of the prevalent use of antibacterial agents. Thus, new antibacterial agents and therapeutics that can treat bacterial infections are necessary. Vancomycin is a potent antibiotic. Unfortunately, some bacterial strains have developed their resistance toward vancomycin. Nevertheless, it has been demonstrated that vancomycin-immobilized nanoparticles (NPs) are capable to be used in inhibition of the cell growth of vancomycin-resistant bacterial strains through multivalent interactions. However, multistep syntheses are usually necessary to generate vancomycin-immobilized NPs. Thus, maintaining the antibiotic activity of vancomycin when the drug is immobilized on the surface of NPs is challenging. In this study, a facile approach to generate vancomycin immobilized gold (Van-Au) NPs through one-pot stirring of vancomycin with aqueous tetrachloroauric acid at pH 12 and 25 °C for 24 h was demonstrated. Van-Au NPs (8.4 ± 1.3 nm in size) were readily generated. The generated Van-Au NPs maintained their antibiotic activities and inhibited the cell growth of pathogens, which included Gram-positive and Gram-negative bacteria as well as antibiotic-resistant bacterial strains. Furthermore, the minimum inhibitory concentration of the Van-Au NPs against bacteria was lower than that of free-form vancomycin. Staphylococcus aureus-infected macrophages were used as the model samples to examine the antibacterial activity of the Van-Au NPs. Macrophages have the tendency to engulf Van-Au NPs through endocytosis. The results showed that the cell growth of S. aureus in the macrophages was effectively inhibited, suggesting the potential of using the generated Van-Au NPs as antibacterial agents for bacterial infectious diseases.
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Hong-Zheng
authors.initials: HZ
authors.lastname: Lai
authors.forename: Wei-Yu
authors.initials: WY
authors.lastname: Chen
authors.forename: Ching-Yi
authors.initials: CY
authors.lastname: Wu
authors.forename: Yu-Chie
authors.initials: YC
authors.lastname: Chen
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D004337:Drug Carriers / Q000737:chemistry* / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D007711:Klebsiella pneumoniae / Q000187:drug effects; D053758:Nanoparticles / Q000737:chemistry*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects; D014640:Vancomycin / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D004337:Drug Carriers; D014640:Vancomycin
keywords: Staphylococcus aureus; antibiotics; gold nanoparticles; macrophage; pathogenic bacteria; vancomycin