Long Passage Times of Short ssDNA Molecules through Metallized Nanopores Fabricated by Controlled Breakdown

作者：Kwok Harold^*; Waugh Matthew; Bustamante Jose; Briggs Kyle; Tabard Cossa Vincent

来源：Advanced Functional Materials, 2014, 24(48): 7745-7753.

DOI：10.1002/adfm.201402468

The fabrication of individual nanopores in metallized dielectric membranes using controlled breakdown directly in solution is described. Nanopores as small as 1.5-nm in diameter are fabricated in Au-coated silicon nitride membranes immersed in 1 M KCl by subjecting them to high electric fields. The physical and electrical characteristics of nanopores produced with this method are presented. The translocation of short single-stranded DNA molecules is demonstrated through such nanopore devices without further passivation of the metallic surface. Metallized nanopores can prolong the translocation times of 50-nt ssDNA fragments by as much as two orders of magnitude, while the slowest events can reach an average speed as slow as 2 nucleotides per millisecond. The mechanism for the long dwell-time distribution is differentiated from prior studies, which relied on friction to slow down DNA, and is attributed to nucleotide-Au interactions.

• 出版日期2014-12-23