Segmentation of 2D Metal-Organic Framework Nanopores for the Detection of Single-Molecule DNA and Peptides.

Precise regulation of the size and structure of nanopores at the atomic and molecular level is crucial for single-molecule sensing. Here, we demonstrate site-specific modulation of nanopores in two-dimensional metal-organic framework (2D MOF) nanosheets, Zr-BTB (BTB = 1,3,5-tris(4-carboxyphenyl)benzene). By postsynthetically bridging neighboring Zr6 clusters in Zr-BTB with HexAc (1,16-hexadecanedioic acid), we achieved partial or complete segmentation of the nanopores, resulting in distinct properties for DNA and peptide single-molecule detection. We confirmed that both collision-induced and translocation-induced current drops are present in the obtained current traces, which may represent a universal characteristic of a 2D nanopore array in single-molecule analysis. Our findings highlight the unique molecular level structural regulation of 2D solid-state nanopores and represent a step toward realizing single-molecule DNA and protein sequencing using 2D nanopore platforms.