Breaking the Size Barrier in Glass Nanopores to 2 nm: A Path to High‐Resolution Biomolecular Fingerprinting

ABSTRACT Glass nanopores have emerged as a promising single‐molecule sensing platform due to their low intrinsic noise, facile fabrication, and excellent integrability. The fabrication of glass nanopores with diameters down to 1–3 nm, a scale comparable to nucleic acids and peptides, is a critical step toward high‐resolution fingerprinting or event sequencing of these molecules, yet it remains a significant challenge. Here, it has overcome this obstacle by direct fabrication of ~2 nm glass nanopores, exemplified by the detection of double‐stranded DNA (dsDNA) with an exceptional signal‐to‐noise ratio (SNR), exhibiting over 80% ionic current blockade. Furthermore, we demonstrate the discrimination of dsDNA as short as 40 base pairs (bp), the differentiation of single‐stranded DNA (ssDNA) homopolymers (40 nucleotides). Finally, it is further highlighted that remarkably superior resolution successfully detects a DNA topological structure containing a 40‐nucleotide (nt) gap within dsDNA, a feature that is extremely challenging to resolve using larger‐diameter glass nanopores. This work marks a milestone in glass nanopores and paves the way for high‐resolution biomolecular sensing, fingerprinting, and even sequencing.