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Continuous differential impedance spectroscopy of single cells.

Malleo D, Nevill JT, Lee LP, Morgan H - Microfluid Nanofluidics (2009)

Bottom Line: Measurements are accomplished by recording the current from two closely-situated electrode pairs, one empty (reference) and one containing a cell.We demonstrate time-dependent measurement of single cell impedance produced in response to dynamic chemical perturbations.ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10404-009-0534-2) contains supplementary material, which is available to authorized users.

View Article: PubMed Central - PubMed

ABSTRACT
A device for continuous differential impedance analysis of single cells held by a hydrodynamic cell trapping is presented. Measurements are accomplished by recording the current from two closely-situated electrode pairs, one empty (reference) and one containing a cell. We demonstrate time-dependent measurement of single cell impedance produced in response to dynamic chemical perturbations. First, the system is used to assay the response of HeLa cells to the effects of the surfactant Tween, which reduces the impedance of the trapped cells in a concentration dependent way and is interpreted as gradual lysis of the cell membrane. Second, the effects of the bacterial pore-forming toxin, Streptolysin-O are measured: a transient exponential decay in the impedance is recorded as the cell membrane becomes increasingly permeable. The decay time constant is inversely proportional to toxin concentration (482, 150, and 30 s for 0.1, 1, and 10 kU/ml, respectively). ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10404-009-0534-2) contains supplementary material, which is available to authorized users.

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Traces of three individual cells showing the typical change in impedance when a single HeLa Cells is perfused with Tween 20 at two different concentrations. a 1% Tween 20 causes a differential /Z/ change (at 300 kHz) of 20–30% in 20–50 s. A transient increase in /Z/ of the order of 5–10% occurs before permeabilization probably due to transient osmotic swelling. b 0.01% Tween 20 causes a differential /Z/ change (at 300 kHz) of 3–5% in 150 s
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Fig5: Traces of three individual cells showing the typical change in impedance when a single HeLa Cells is perfused with Tween 20 at two different concentrations. a 1% Tween 20 causes a differential /Z/ change (at 300 kHz) of 20–30% in 20–50 s. A transient increase in /Z/ of the order of 5–10% occurs before permeabilization probably due to transient osmotic swelling. b 0.01% Tween 20 causes a differential /Z/ change (at 300 kHz) of 3–5% in 150 s

Mentions: In order to demonstrate cell lysis, HeLa cells were captured in the traps and perfused with PBS containing different concentrations of Tween. The effect of different concentrations of Tween on the magnitude of the impedance (measured at 300 kHz) is shown in Fig. 5. A solution of 1% w/w causes complete cell lysis resulting in a large sudden decrease in impedance magnitude (25% over 10 s), Fig. 5a. Prior to lysis, there is a short increase in the impedance, which is attributed to swelling of the cell (this was confirmed optically). Presumably, water enters the cell through the disrupted membrane, and then the cell bursts. A lower concentration of Tween (0.01% w/w) causes a gradual decrease in the impedance (4% over 100 s), as shown in Fig. 5b.Fig. 5


Continuous differential impedance spectroscopy of single cells.

Malleo D, Nevill JT, Lee LP, Morgan H - Microfluid Nanofluidics (2009)

Traces of three individual cells showing the typical change in impedance when a single HeLa Cells is perfused with Tween 20 at two different concentrations. a 1% Tween 20 causes a differential /Z/ change (at 300 kHz) of 20–30% in 20–50 s. A transient increase in /Z/ of the order of 5–10% occurs before permeabilization probably due to transient osmotic swelling. b 0.01% Tween 20 causes a differential /Z/ change (at 300 kHz) of 3–5% in 150 s
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2944380&req=5

Fig5: Traces of three individual cells showing the typical change in impedance when a single HeLa Cells is perfused with Tween 20 at two different concentrations. a 1% Tween 20 causes a differential /Z/ change (at 300 kHz) of 20–30% in 20–50 s. A transient increase in /Z/ of the order of 5–10% occurs before permeabilization probably due to transient osmotic swelling. b 0.01% Tween 20 causes a differential /Z/ change (at 300 kHz) of 3–5% in 150 s
Mentions: In order to demonstrate cell lysis, HeLa cells were captured in the traps and perfused with PBS containing different concentrations of Tween. The effect of different concentrations of Tween on the magnitude of the impedance (measured at 300 kHz) is shown in Fig. 5. A solution of 1% w/w causes complete cell lysis resulting in a large sudden decrease in impedance magnitude (25% over 10 s), Fig. 5a. Prior to lysis, there is a short increase in the impedance, which is attributed to swelling of the cell (this was confirmed optically). Presumably, water enters the cell through the disrupted membrane, and then the cell bursts. A lower concentration of Tween (0.01% w/w) causes a gradual decrease in the impedance (4% over 100 s), as shown in Fig. 5b.Fig. 5

Bottom Line: Measurements are accomplished by recording the current from two closely-situated electrode pairs, one empty (reference) and one containing a cell.We demonstrate time-dependent measurement of single cell impedance produced in response to dynamic chemical perturbations.ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10404-009-0534-2) contains supplementary material, which is available to authorized users.

View Article: PubMed Central - PubMed

ABSTRACT
A device for continuous differential impedance analysis of single cells held by a hydrodynamic cell trapping is presented. Measurements are accomplished by recording the current from two closely-situated electrode pairs, one empty (reference) and one containing a cell. We demonstrate time-dependent measurement of single cell impedance produced in response to dynamic chemical perturbations. First, the system is used to assay the response of HeLa cells to the effects of the surfactant Tween, which reduces the impedance of the trapped cells in a concentration dependent way and is interpreted as gradual lysis of the cell membrane. Second, the effects of the bacterial pore-forming toxin, Streptolysin-O are measured: a transient exponential decay in the impedance is recorded as the cell membrane becomes increasingly permeable. The decay time constant is inversely proportional to toxin concentration (482, 150, and 30 s for 0.1, 1, and 10 kU/ml, respectively). ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10404-009-0534-2) contains supplementary material, which is available to authorized users.

No MeSH data available.


Related in: MedlinePlus