title: Enhanced antibacterial activity of amino acids-functionalized multi walled carbon nanotubes by a simple method.
abstract: Multi-walled carbon nanotubes (MWCNTs) were first functionalized by arginine and lysine under microwave radiation. Surface functionalization was confirmed by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and transmission electron microscopy (TEM). After the MWCNTs were functionalized by arginine and lysine, the antibacterial activity of all treated samples was increased significantly against all bacteria that were tested. Based on the observed minimum inhibitory concentration and radial diffusion assay, the sequence of antibacterial activity was MWCNTs-arginine>MWCNTs-lysine>pristine MWCNTs. The functionalized MWCNTs were especially effective against gram-negative bacteria (e.g., Escherichia coli and Salmonella typhimurium). Interestingly, the MWCNT samples were effective against the resistant strain Staphylococcos aureus. The enhanced antibacterial activity was attributed to electrostatic adsorption of bacteria membrane due to positive charges of the functional groups on MWCNTs surface. Since MWCNTs have lower cytotoxicity than single-walled carbon nanotubes, their functionalization with cationic amino acids could be a beneficial approach in the disinfection industry.
authors.affiliation: Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: Hadi Zare
authors.initials: HZ
authors.lastname: Zardini
authors.forename: Ahmad
authors.initials: A
authors.lastname: Amiri
authors.forename: Mehdi
authors.initials: M
authors.lastname: Shanbedi
authors.forename: Morteza
authors.initials: M
authors.lastname: Maghrebi
authors.forename: Majid
authors.initials: M
authors.lastname: Baniadam
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D008826:Microbial Sensitivity Tests / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D012486:Salmonella typhimurium / Q000187:drug effects; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000596:Amino Acids; D000900:Anti-Bacterial Agents; D037742:Nanotubes, Carbon