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bioRxiv · 10.64898/2026.07.20.739564

Nanopore Electrometry Resolves Peptide Charge Patterns beyond Ionic-Current Blockade

Sur, P.·Maiti, P. K.·Varma, M. M.
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Abstract

Localized measurements of electric fields offer a promising route to expand the information content of nanopore-based single-molecule sensing beyond conventional ionic-current blockade. Here, using all-atom molecular dynamics simulations with virtual electric-field probes placed around a graphene nanopore, we show that the local electric-field captures the presence, and distribution of charged amino acids as the peptides translocate through the pore. These field signatures create reproducible peptide-specific fingerprints across independent translocation events and enable substantially improved discrimination between peptides compared with ionic-current traces obtained under the same simulation conditions. Our results suggest that localized nanopore electrometry can provide a complementary, information-rich readout of peptide charge order that is largely inaccessible to conventional current blockade-based measurement. This study establishes a simulation-guided framework for integrating nanoscale electrometry with nanopore platforms for future peptide and protein analysis.

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Sur, P., Maiti, P. K., Varma, M. M.. 2026-07-23. Nanopore Electrometry Resolves Peptide Charge Patterns beyond Ionic-Current Blockade. https://doi.org/10.64898/2026.07.20.739564

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