Mechanism of the toxic action of copper nanoparticles on Escherichia coli bacteria
Volodina, L.A.; Zhigach, A.N.; Leĭpunskiĭ, I.O.; Fedorov, I.I.; Glushchenko, N.N.
Biofizika 54(6): 1060-1065
2009
ISSN/ISBN: 0006-3029 PMID: 20067188 Document Number: 629167
Some features of contact interaction of Escherichia coli with Cu nanoparticles 75-100 nm in diameter have been studied. The analysis of variations in the amplitude of fluorescence of the negatively charged probe 1-anilinonaphthalene-8-sulfonate (ANS) in Gouy-Chapmen coordinates indicates an increase (in the absolute value) in the electrostatic potential of E. coli external membrane during the contact with Cu nanoparticles. The increase in the electrostatic potential correlates with the bacteriostatic influence on the growth of bacterial population. The calculations of tryptophan fluorescence quenching by iodide in the presence of Cu nanoparticles with the use of the Stern-Volmer equation revealed an increase in the constant of dynamic quenching and the availability of the fluorophore to suppressor.