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Single nanopore has drawn wide attention due to its potentials for DNA sequencing,single molecule detection,molecular transport studies,etc.Mainly two types of nanopores can be recognized: soft nanopore established on lipid membrane by pore proteins,such as alpha-HL; solid artificial pore of inorganic or organic polymer substrate.Solid artificial pore is preferred for it stability and size tuning possibility.Heavy ion irradiation is often used to generate single nanopres on polymer membrane,and the pores can be tuned by post chemical etching.Inorganic substrates include Si,SiN,glass etc.Usually sophisticated and professional microfabrication facilities have to be involved,such as photolithography,focused ion beam (FIB),tunnel electronic microscope (TEM),etc.Glass substrate have unique optical,electrical and chemical properties,nanochannles can be established by incorporation of conventional photolithographic process and FIB etching.Single nanopore can also be formed at the end of fused silica capillary,with which high aspect ratio nano tip pipette can be obtained.Nanofracture can also be introduced onto the capillary,and efficient electrokinetic stacking of DNA has been well demonstrated [1-2].An ion conductive interface can also be introduced by HF etching of the capillary wall,and nanofluidic effect based biomolecules concentration can be achieved [3].To date,most reported nanofluidic interfaces are constructed by microfabricated nanochannel(s) or membranes with multiple nanopores across microchannels,truly single nanopore based assay of biomolecules was seldom seen in the literature.In this work,we demonstrate that single nanopore can be formed directly on the fused silica capillary by careful control of the etching process,and the pore size (correlated with electrolyte conductance) could be tuned by controlled over etching (Figure.1).Single nanopoe based electrokinetic stacking of DNA was achieved,and simultaneous staining of DNA local at the nanopoe was also demonstrated (Figure.2).Preliminary tests show that various single nanopore assays could be performed based on this low aspect ratio solid state single nanopore at the bottom of a bowl shape micro cavity,which also exhibit current rectification and nanoparticle/molecule translocation effect.This work shows that,single nanopore can be generated on fused silica capillary without sophisticated nanofabrication,and multiple nanofluidic assays could be implemented with this platform.