Lifetime of glass nanopores in a PDMS chip for single-molecule sensing.

Nanopore sensing is an emerging technology that has many biosensing applications ranging from DNA sequencing using biological pores to biomolecular analysis using solid-state pores. Solid-state nanopores that are more stable are an attractive choice for biosensing applications. Still, biomolecule interactions with the nanopore surface reduce nanopore stability and increase usage costs. In this study, we investigated the biosensing capability for 102 quartz glass nanopores with a diameter of 11-18 nm that were fabricated using laser-assisted capillary pulling. Nanopores were assembled into multiple microfluidic chips that were repeatedly used for up to 19 weeks. We find that using vacuum storage combined with minimal washing steps improved the number of use cycles for nanopores. The single-molecule biosensing capability over repeated use cycles was demonstrated by quantitative analysis of a DNA carrier designed for detection of short single-stranded DNA oligonucleotides.