DNA manipulation by means of insulator‐based dielectrophoresis employing direct current electric fields

Abstract

Electrokinetic techniques offer a great potential for biological particle manipulation. Among these, dielectrophoresis (DEP) has been successfully utilized for the concentration of bioparticles. Traditionally, DEP is performed employing microelectrodes, an approach with attractive characteristics but expensive due to microelectrode fabrication costs. An alternative is insulator-based DEP, a method where non-uniform electric fields are created with arrays of insulating structures. This study presents the concentration of linear DNA particles (pET28b) employing a microchannel, with an array of cylindrical insulating structures and direct current electric fields. Results showed manipulation of DNA particles with a combination of electroosmotic, electrophoretic, and dielectrophoretic forces. Employing suspending media with conductivity of 104 muS/cm and pH of 11.15, under applied fields between 500 and 1500 V/cm, DNA particles were observed to be immobilized due to negative dielectrophoretic trapping. The observation of DNA aggregates that occurred at higher applied fields, and dispersed once the field was removed is also included. Finally, concentration factors varying from 8 to 24 times the feed concentration were measured at 2000 V/cm after concentration time-periods of 20-40 s. The results presented here demonstrate the potential of insulator-based DEP for DNA concentration, and open the possibility for fast DNA manipulation for laboratory and large-scale applications.

Floating-electrode enhanced constriction dielectrophoresis for biomolecular trapping in physiological media of high conductivity

“…1932-1058/2012/6(1)/012806/14/$30.00 V C 2012 American Institute of Physics 6, 012806-1 double-stranded (ds-DNA), ss-DNA target molecules, [16][17][18][19] and RNA (Ribonucleic acid) species. 20 However, DEP trapping within media of high conductivity for enhancement of DNA hybridization kinetics poses distinct challenges.…”

Modelling of electrokinetic phenomena for capture of PEGylated ribonuclease A in a microdevice with insulating structures

“…The insulating structures deform the electric field creating non-uniform DC fields that polarize particles. 9 So far, we have demonstrated that mono-PEG and di-PEG RNase A conjugates can be captured and concentrated in one single step at different voltages using iDEP microchannels, while the native protein is not captured at any of the conditions tested. 15 Nonetheless, in our previous work, we did not describe the electrokinetic phenomena involved in this system.…”

“…EK phenomena have been successfully employed within microfluidic systems to manipulate the movement of a range of bioparticles, among which we can list yeast cells, virus, bacteria, microalgae, and DNA. 6,[9][10][11] Hence, an alternative strategy that can be exploited for the manipulation of proteins is the use of EKs in microfluidic devices. Although microfluidic devices offer advantages like portability and reduced analysis time, 12 their use is still far from being a routine technique such as chromatography-based methods, especially for protein recovery.…”

Microfluidic bio-particle manipulation for biotechnology

“…height of the electrodes are in the order of hundred nanometers), and are fabricated within the device by means of complex, time consuming and relatively expensive manufacturing techniques such as thin-film deposition, sputtering, chemical vapor deposition, etc. Moreover, fouling of the electrodes may distort the operation of the device when working with bio-particles [43]. However, with an appropriate design (i.e.…”