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Using Impedance Flow Cytometry for Rapid Viability Classification of Heat-Treated Bacteria.

ABSTRACT: In the future, rapid electrical characterization of cells with impedance flow cytometry promises to be a fast and accurate method for the evaluation of cell properties. In this paper, we investigate how the conductivity of the suspending medium along with the heat exposure time affects the viability classification of heat-treated E. coli. Using a theoretical model, we show that perforation of the bacteria membrane during heat exposure changes the impedance of the bacterial cell from effectively less conducting than the suspension medium to effectively more conducting. Consequently, this results in a shift in the differential argument of the complex electrical current that can be measured with impedance flow cytometry. We observe this shift experimentally through measurements on E. coli samples with varying medium conductivity and heat exposure times. We show that increased exposure time and lower medium conductivity results in improved classification between untreated and heat-treated bacteria. The best classification was achieved with a medium conductivity of 0.045 S/m after 30 min of heat exposure.

SUBMITTER: Bertelsen CV

PROVIDER: S-EPMC9979241 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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Using Impedance Flow Cytometry for Rapid Viability Classification of Heat-Treated Bacteria.

Bertelsen Christian Vinther CV Skands Gustav Erik GE González Díaz Marcos M Dimaki Maria M Svendsen Winnie Edith WE

ACS omega 20230216 8

In the future, rapid electrical characterization of cells with impedance flow cytometry promises to be a fast and accurate method for the evaluation of cell properties. In this paper, we investigate how the conductivity of the suspending medium along with the heat exposure time affects the viability classification of heat-treated <i>E. coli</i>. Using a theoretical model, we show that perforation of the bacteria membrane during heat exposure changes the impedance of the bacterial cell from effec ...[more]

PMID: 36873038

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Dataset Information

Using Impedance Flow Cytometry for Rapid Viability Classification of Heat-Treated Bacteria.

Publications

Using Impedance Flow Cytometry for Rapid Viability Classification of Heat-Treated Bacteria.

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