Carbon Nanotubes as Electrodes for Dielectrophoresis of DNA

TL;DR

This paper demonstrates that carbon nanotube electrodes enable efficient dielectrophoretic trapping of nanoscale DNA molecules at low voltages, outperforming traditional metallic electrodes, with insights gained through simulations of DNA polarizability.

Contribution

It introduces the use of carbon nanotube electrodes for dielectrophoresis of DNA, showing improved trapping efficiency and providing analysis of DNA polarizability.

Findings

Carbon nanotube electrodes allow low-voltage trapping of nanoscale DNA.

Enhanced field gradients improve dielectrophoretic efficiency.

Simulation reveals frequency-dependent DNA polarizability.

Abstract

Dielectrophoresis can potentially be used as an efficient trapping tool in the fabrication of molecular devices. For nanoscale objects, however, the Brownian motion poses a challenge. We show that the use of carbon nanotube electrodes makes it possible to apply relatively low trapping voltages and still achieve high enough field gradients for trapping nanoscale objects, e.g., single molecules. We compare the efficiency and other characteristics of dielectrophoresis between carbon nanotube electrodes and lithographically fabricated metallic electrodes, in the case of trapping nanoscale DNA molecules. The results are analyzed using finite element method simulations and reveal information about the frequency dependent polarizability of DNA.