Theoretical studies on key factors in DNA sequencing using atomically thin molybdenum disulfide nanopores

Nanopore-based DNA sequencing is considered to be a low-cost, high resolution and superfast method. Solid state nanopores, especially MoS2 nanopores, have been considered to be a promising choice for DNA sequencing. However, researchers still have a very limited understanding of the effects of multiple factors on MoS2-based DNA sequencing. In this study, the effects of the applied voltage and the diameter of the MoS2 nanopore on the resolution of DNA sequencing were investigated. Our results demonstrate that the translocation time of DNA can increase with a decrease in the applied voltage. DNA can be stretched significantly to translocate a 2 nm nanopore under a high applied voltage (>400 mV nm-1). To achieve a 1 base per μs translocation speed (1 GHz bandwidth), we suggest that three methods could be applied, including a decrease in the applied voltage, a decrease in the diameter of the MoS2 nanopore or modification of the MoS2 nanopore. In addition, the size of the nanopore can severely affect the possibility of DNA entering the nanopore, and the translocation time of DNA could be significantly increased with a smaller MoS2 nanopore. These findings may help to design MoS2 nanopores with higher resolution for use in DNA sequencing.