Establishment of the ac electrokinetic elongation mechanism of DNA by three-dimensional fluorescent imaging

Wälti, Christoph; Tosch, P.; Davies, A. G.; Germishuizen, W. A.; Kaminski, Clemens F.

doi:10.1063/1.2188587

Cited by 16 publications

(18 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This effect was attributed to the global polarizability of a coil at low frequencies [1, 2], and the high local anisotropy of the counterion transport at high frequencies [3, 4]. Here we show that the behavior is drastically different at frequencies at which the counter-ion relaxation length scale matches the scale of internal density fluctuations.…”

mentioning

confidence: 72%

Collapse of DNA in ac Electric Fields

et al. 2011

View full text Add to dashboard Cite

We report that double-stranded DNA collapses in presence of a.c. electric fields at frequencies of a few hundred Hertz, and does not stretch as commonly assumed. In particular, we show that confinement-stretched DNA can collapse to about one quarter of its equilibrium length. We propose that this effect is based on finite relaxation times of the counterion cloud, and the subsequent partitioning of the molecule into mutually attractive units. We discuss alternative models of those attractive units.

show abstract

mentioning

confidence: 72%

Collapse of DNA in ac Electric Fields

et al. 2011

View full text Add to dashboard Cite

show abstract

“…Initial single-molecule observations reported a stretching along the direction of the a.c. electric field at a few MHz for tethered molecules. 1–3 Simulations of short segments of free polyelectrolytes in electric fields appeared to show the same effect. 4 …”

Section: Introductionmentioning

confidence: 78%

Collapse of DNA under alternating electric fields

Zhou

Riehn

2015

Phys. Rev. E

View full text Add to dashboard Cite

Recent studies have shown that double-stranded DNA can collapse in presence of a strong electric field. Here we provide an in-depth study of the collapse of DNA under weak confinement in microchannels as a function of buffer strength, driving frequency, applied electric field strength, and molecule size. We find that the critical electric field at which DNA molecules collapse (10s of kV/cm) is strongly dependent on driving frequency dependent (100 … 800 Hz) and molecular size (20 … 160 kbp), and weakly dependent on the ionic strength (8 … 60 mM). We argue that an apparent stretching at very high electric fields is an artifact of the finite frame time of video microscopy. PACS numbers: 87.14.gk, 36.20.Ey, 82.35.Lr, 82.35.Rs

show abstract

“…Beyond a threshold voltage, the torque and electrothermal forces on the DNA molecules become dominant and they together induce a motion on the DNA molecules that would move the molecules away from the electrodes. 14 Figure 6 shows the velocity of the DNA molecules at the center of the channel for various applied voltages and at a distance of 1110 m away from the center of the electrode gap. The velocity of DNA molecules increases with the applied voltage since the amount of torque experienced by the DNA molecules is proportional to the electric field.…”

Section: Electrokinetic Dna Stretchingmentioning

confidence: 99%

Integration of electrodes in Si channels using low temperature polymethylmethacrylate bonding

Dukkipati

Pang

2007

Journal of Vacuum Science &Amp; Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena

View full text Add to dashboard Cite

Low temperature Si to glass bonding using polymethylmethacrylate (PMMA) as an adhesive layer is developed to integrate electrodes with Si channels. The integrated microsystem contains channels dry etched in Si with widths ranging from 3to100μm and depths ranging from 100nmto30μm. The channels are bonded to a 100μm thick glass consisting of 600nm thick patterned PMMA and 20∕50nm thick Cr∕Au electrodes, with PMMA as an adhesive layer. The typical bond strength is 3MPa, obtained by bonding at 110°C with 600nm thick PMMA. Fluidic flow studies are carried out in channels that are 50 and 100μm wide with a depth of 100nm. De-ionized water flows through the sealed Si channels due to capillary pressure with an initial velocity of 0.65mm∕s for 50μm wide and 100nm deep channels. Electric fields are used to induce DNA motion with velocities from 2.4to14.5μm∕s in 100μm wide and 20μm deep channels. The forces generated by the fields and the fluid flow are also used to stretch the tethered DNA molecules up to 15μm long in the microchannels.

show abstract

Establishment of the ac electrokinetic elongation mechanism of DNA by three-dimensional fluorescent imaging

Cited by 16 publications

References 24 publications

Collapse of DNA in ac Electric Fields

Collapse of DNA in ac Electric Fields

Collapse of DNA under alternating electric fields

Integration of electrodes in Si channels using low temperature polymethylmethacrylate bonding

Contact Info

Product

Resources

About