Seung Kyu Min‡, Woo Youn Kim†‡, Yeonchoo Cho and Kwang S. Kim*
Center for Superfunctional Materials, Department of Chemistry and Department of Physics, Pohang University of Science and Technology, Hyojadong, Namgu, Pohang 790-784, Korea; †Present address: Department of Chemistry, KAIST, Daejeon 305-701, Korea; ‡These authors contributed equally to this work.
Devices in which a single strand of DNA is threaded through a nanopore could be used to efficiently sequence DNA1-9. However, various issues will have to be resolved to make this approach practical, including controlling the DNA translocation rate, suppressing stochastic nucleobase motions, and resolving the signal overlap between different nucleobases4,7. Here, we demonstrate theoretically the feasibility of DNA sequencing using a fluidic nanochannel functionalized with a graphene nanoribbon. This approach involves deciphering the changes that occur in the conductance of the nanoribbon10,11 as a result of its interactions with the nucleobases via π–π stacking12,13. We show that as a DNA strand passes through the nanochannel14, the distinct conductance characteristics of the nanoribbon15-17 (calculated using a method based on density functional theory coupled to non-equilibrium Green function theory18-20) allow the different nucleobases to be distinguished using a data-mining technique and a two-dimensional transient autocorrelation analysis. This fast and reliable DNA sequencing device should be experimentally feasible in the near future.