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Dielectrophoretic separation of bacteria using a conductivity gradient.

G H Markx·P A Dyda·R Pethig
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Abstract

Dielectrophoresis, the lateral motion induced on particles by non-uniform electric fields, is a sensitive function of the electrical conductivity of the particle suspending medium. This dependence is exploited in a new technique for separating bioparticles from suspended mixtures. The bioparticles are first immobilised by positive dielectrophoresis at electrodes in a separation chamber, and the conductivity of the liquid flowing through the chamber is then gradually and continuously increased so as to produce a conductivity gradient with time. The bioparticles are released from the electrodes according to their own dielectric properties and as a function of flow rate and medium conductivity. This is demonstrated for pure suspensions and mixtures of the bacteria Bacillus subtilis, Escherichia coli and Micrococcus luteus.

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Bacillus subtilisBacteriaBiotechnologyElectric ConductivityElectrophoresisEscherichia coliMicrococcus luteusJournal ArticleResearch Support, Non-U.S. Gov't

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G H Markx, P A Dyda, R Pethig. 1996-11-01. Dielectrophoretic separation of bacteria using a conductivity gradient.. https://doi.org/10.1016/0168-1656(96)01617-3

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