Fine tuning of nanopipettes using XXXX for single molecule sensing.

@entity5383 @entity16773 @entity655
UNASSIGNED: Nanopipettes are an attractive single-molecule tool for identification and characterisation of nucleic acids and proteins in solutions. They enable label-free analysis and reveal individual molecular properties, which are generally masked by ensemble averaging. Having control over the pore dimensions is vital to ensure that the dimensions of the molecules being probed match those of the pore for optimization of the signal to noise. Although nanopipettes are simple and easy to fabricate, challenges exist, especially when compared to more conventional solid-state analogues. For example, a sub-20 nm pore diameter can be difficult to fabricate and the batch-to-batch reproducibility is often poor. To improve on this limitation, @entity655 ( @entity655 ) is used to deposit ultrathin layers of @entity5383 ( @entity16773 ) on the surface of the quartz nanopipettes enabling sub-nm tuning of the pore dimensions. Here, @entity16773 with a thickness of 8, 14 and 17 nm was deposited onto pipettes with a starting pore diameter of 75    5 nm whilst a second batch had 5 and 8 nm @entity16773 deposited with a starting pore diameter of 25    3 nm respectively. This highly conformal process coats both the inner and outer surfaces of pipettes and resulted in the fabrication of pore diameters as low as 7.5 nm. We show that @entity16773 modified pores do not interfere with the sensing ability of the nanopipettes and can be used for high signal-to-noise DNA detection. @entity655 provides a quick and efficient (batch processing) for fine-tuning nanopipettes for a broad range of applications including the detection of small biomolecules like RNA, aptamers and DNA-protein interactions at the single molecule level.
