Fabrication of double conical PET nanochannel for molecular detection

Polymer nanochannels based on ion-track etching have attracted increasing interests for molecule detection using current blockage because of the easy control of nanochannel with precise geometry at 1 nm scale in recent years. In this work, polyethylene terephthalate (PET) membranes were irradiated with single ions of 2.15 GeV Kr and then the single latent ion track was developed to fabricate nanochannels of several nanometers for lambda-DNA detection. The ion-track etching with DC or AC provided reliable fabrication of double conical nanochannel with similar size of 48 kb λDNA with symmetrical ion transportation. Current blockage experiments demonstrated that the bi-conical PET nanochannel is sensitive for the translocation of 48 kb λDNA biomolecules with the mean translocation blockage factor Δi/i from 0.02 to 0.10 and the ability to differentiate the number of molecules. The nanochannel is more sensitive for biomolecule detection at lower KCl concentration. This investigation demonstrates that latent track etching of energetic heavy ions is a reliable approach in polymer nanochannel fabrication for biomolecule detection with accurate nanoscale control and low-cost mass production. •Precise polymer nanochannel of 1nm sacle fabricated by track etching of single Kr ion.•First report on biconical nanopore for biomolecule detection which located in the middle of the PET membrane instead of the membrane surface so that the nanopore is more robust for the measurement.•report on the sensitive detection of lambda-DNA using ionic current blockage measurement and the translocation behavior in the ion-track etched nanopores.