DNA translocation through a nanopore in a single-layered doped semiconductor membrane.

Recently, we developed a computational model that allowed us to study the influence a semiconductor membrane has on a DNA molecule translocating through a nanopore in this membrane. Our model incorporated both the self-consistent Poisson-Nernst-Planck simulations for the electric potential of a solid state membrane immersed in an electrolyte solution together with the Brownian dynamics of the biomolecule. In this paper, we study how the applied electrolyte bias, the semiconductor membrane bias, and the semiconductor material type (n-Si or p-Si) affect the translocation dynamics of a single-stranded DNA moving through a nanopore in a single-layered semiconductor membrane. We show that the type of semiconductor material used for the membrane has a prominent effect on the biomolecule's translocation time, with DNA exhibiting much longer translocation times through the p-type membrane than through the n type at the same electrolyte and membrane potentials, while the extension of the biomolecule remains practically unchanged. In addition, we find the optimal combination for the membrane-electrolyte system's parameters to achieve the longest translocation time and largest DNA extension. With our single-layered electrically tunable membranes, the DNA translocation time can be manipulated to have an order of magnitude increase.