MoS2 is also a single-layer sheet, thin enough that only one DNA letter at a time goes through the nanopore. In the study, the Illinois researchers found that DNA does not stick to MoS2, but threads through the pore cleanly and quickly. See an animation online at https://www.youtube.com/watch?v=DVh-TT507rg.
"MoS2 is a competitor of graphene in terms of transistors, but we showed here a new functionality of this material by showing that it is capable of biosensing," said graduate student Amir Barati Farimani, the first author of the paper.
Most exciting for the researchers, the simulations yielded four distinct signals corresponding to the bases in a double-stranded DNA molecule. Other systems have yielded two at best A/T and C/G which then require extensive computational analysis to attempt to distinguish A from T and C from G.
The key to the success of the complex MoS2 simulation and analysis was the Blue Waters supercomputer, located at the National Center for Supercomputing Applications at the U. of I.
"These are very detailed calculations," said Aluru, who is also a part of the Beckman Institute for Advanced Science and Technology at the U. of I. "They really tell us the physics of the actual mechanisms, and why MoS2 is performing better than other materials. We have those insights now because of this work, which used Blue Waters extensively."
Now, the researchers are exploring whether they can achieve even greater performance by coupling MoS2 with another material to form a low-cost, fast and accurate DNA sequencing device.
"The ultimate goal of this research is to make some kind of home-based or personal DNA sequencing device," Barati Farimani said. "We are on the path to get there, by finding the technologies that can quickly, cheaply and accurately identify the human genome. Having a map of your DNA can
|Contact: Liz Ahlberg|
University of Illinois at Urbana-Champaign