Accession Number : ADA621076


Title :   Antimicrobial Effects of Gold/Copper Sulphide (Au/Cus) Core/Shell Nanoparticles on Bacillus Anthracis Spores and Cells


Descriptive Note : Master's thesis


Corporate Author : NORTH CAROLINA CENTRAL UNIV DURHAM


Personal Author(s) : Addae, Ebenezer


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a621076.pdf


Report Date : Jan 2013


Pagination or Media Count : 62


Abstract : Bacillus anthracis is a gram positive, rod shaped and spore forming bacteria. It causes anthrax, a deadly human and animal disease that can kill its victims in three days. The spores of B. antrhacis can survive extreme environmental conditions for decades and germinate when exposed to proper conditions. Due to its potential as a bio-weapon, effective disinfectants that pose less harm to the environment and animals are urgently needed. Metal nanoparticles have the potential of killing microbial cells and spores. We present here the effect of Gold/Copper Sulphide core/shell (Au/CuS) nanoparticles on B. anthracis cells and spores. The results indicated that the continuous presence of 0.83 micrometers during the spore growth in nutrient medium completely inhibited spore outgrowth. Au/CuS nanoparticles at concentration of 4.15 micrometers completely inactivated B. anthracis cells (x 10(exp7)) after 30 min of pre-treatment in any of the three buffers including water, PBS, and nutrient broth. However, the same and even higher concentrations of nanoparticles produce no significant spore (x 10(exp5)) killing after 24 h of pre-treatment. SEM imaging, EDS analysis, and DNA extrusion experiments revealed that nanoparticles damaged the cell membrane causing DNA and cytosolic content efflux and eventually cell death. The study demonstrated the strong antimicrobial activity of Au/CuS nanoparticles to B. anthracis cells and revealed that Au/CuS NPs showed more effective inactivation effect against the cells than they did against the spores.


Descriptors :   *ANTIMICROBIAL AGENTS , *BACILLUS ANTHRACIS , *DISINFECTION , *NANOPARTICLES , *SPORES , ANTHRAX , BIOLOGICAL INACTIVATION , BIOLUMINESCENCE , BIOTERRORISM , CONCENTRATION(COMPOSITION) , COPPER SULFIDES , DEOXYRIBONUCLEIC ACIDS , EXPOSURE(PHYSIOLOGY) , GOLD COMPOUNDS , GRAM POSITIVE BACTERIA , GROWTH(PHYSIOLOGY) , KILL PROBABILITIES , MEMBRANES(BIOLOGY) , MICROORGANISMS , PHOSPHATES , SHELLS(STRUCTURAL FORMS) , THESES , TRANSMISSION ELECTRON MICROSCOPY , VACCINES


Subject Categories : Microbiology
      Pharmacology


Distribution Statement : APPROVED FOR PUBLIC RELEASE