Capacitance Cytometry

They found that there is a linear relationship between the capacitance and the DNA content of a cell. And they further showed that this relationship is not species dependent. This itmovative technique is termed as capacitance cytometry, which helps to reveal changes in cellular internal properties and determine the phase of individual cell in cell cycle. 

Sohn LL, Saleh OA, Facer GR, Beavis AJ, Allan RS, Notteiman DA (2000) Capacitance cytometry measuring biological cells one by one. Proc Natl Acad Sci U S A 97 10687-10690... 

Sohn and co-workers reported a novel device which can quantify the DNA content within the nucleus of single eukaryotic cells [3]. Since DNA molecules are highly charged in intracellular environment, they will he polarized in an applied low-frequency AC electric field. This polarization response can he measured as a change in total capacitance ACj, across a pair of microelectrodes as individual cells suspended in buffer solution flow one by one through a microchannel (as shown in Fig. 1 and Fig. 2). They found that there is a linear relationship between the capacitance and the DNA content of a cell. And they further showed that this relationship is not species-dependent. This innovative technique is termed as capacitance cytometry, which helps to reveal changes in cellular internal properties and determine the phase of individual cell in cell-cycle. 

In addition to the use of electrophoresis for identification of the characteristic DNA ladders, DNA content analysis by flow cytometry is often employed to identify cells undergoing DNA fragmentation. This method is based on the fact that permeabilized apoptotic cells release fragmented DNA, resulting in a DNA content that is less than that in live diploid cells. Sohn et al. [10] developed a novel microfluidic technique - capacitance cytometry -that can be used to quantify the polarization response of... 

Another flow cytometry study involved the measurement of capacitance changes due to varied amounts of polarizable cellular DNA [884],... 

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