Low frequency electric polarizability and zeta-potential of Escherichia coli HB101 (K-12) cells during inactivation with ethanol

Abstract

The electric properties of bacteria determine their non-specific interactions with the environment, in particular their pathogenic activity. The electric polarizability of Escherichia coli HB101 (K-12 strain) was studied while inactivation with ethanol (20–40 vol.%). The current investigation might be regarded as a continuation of previous research on the polarizability of E. coli at lower ethanol concentration (≤ 20 vol.%) and higher frequencies (≥ 20 kHz). The bacteria polarizability at low frequencies (4 Hz) shows anomalies (unexpected increase in the polarizability at certain ethanol concentrations), while the parameter decreases with an increase in the ethanol concentration at higher frequencies. We investigated for the possible reasons causing the anomalies — in our case reduced to the medium dielectric permittivity, the average cell length and the surface electric charge density distribution, related to bacterial lipopolysaccharides. We suggest a hypothesis for the molecular mechanism of changing the surface charge of E. coli, carried by lipopolysaccharides, induced by the non-ionic ethanol.

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Ag2[Fe(CN)5NO]-Fabricated Hydrophobic Cotton as a Potential Wound Healing Dressing: An In Vivo Approach

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“…53 Previously reported studies exhibited that the DLS technique was used to examine the bacterial cell membrane damage by the nanoparticles (especially Ag). 54,55 These studies encouraged us to perform the DLS examination (hydrodynamic diameters and zeta potentials) for determining the bacterial membrane features after treatment with SNPCFs. The surface charge is an important factor for dispersion or aggregation of particles.…”

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