title: Effect of biocide concentration on electrorotation spectra of yeast cells.
abstract: The effect of the biocide Cosmocil (polyhexanide) at different concentrations on the electrorotation spectra of yeast cells is investigated over the frequency range from 1 kHz to 10 MHz. The dielectric properties of the yeast, before and after biocide treatment, were deduced from the electrorotation spectra using two-shell ellipsoid modelling methods that have been well tested for other heterogeneous biological systems. The results show a gradual increase in the cytoplasmic membrane conductivity with increasing biocide concentration, rather than an "all-or-nothing' breakdown of the membrane. The technique gives a quantitative analysis of the toxic damage by chemicals to cells and can be exploited in the development of new pharmacological agents.
authors.affiliation: Institute of Molecular and Biomolecular Electronics, University of Wales, Bangor, Gwynedd, UK.
authors.forename: X F
authors.initials: XF
authors.lastname: Zhou
authors.forename: G H
authors.initials: GH
authors.lastname: Markx
authors.forename: R
authors.initials: R
authors.lastname: Pethig
mesh_terms: D001645:Biguanides / Q000494:pharmacology*; D004560:Electricity; D004566:Electrodes; D004594:Electrophysiology; D008433:Mathematics; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000187:drug effects*
chemical_list: D001645:Biguanides; C031233:polihexanide