Study on the self-assembly and signal amplification ability of nucleic acid nanostructure with the nanopipette

Nanopipette as a member of solid-state nanopores has been developed to detect a set of biological molecules. Although the size of the nanopipette can be adjusted artificially, the direct detection of small molecules is still challenging, which is limited by the precision of the nanopipette preparation. In this work, the translocation characteristics of DNA tetrahedrons with varying degrees of the assembly were studied to evaluate their self-assembly process and the advantage of tetrahedral DNA nanostructures as a signal amplification label for biomarkers detection based on current blockages. Self-assembly of different number of single-stranded DNA causes the DNA nanostructure in different shapes. Through the complete assembly of DNA tetrahedron, we demonstrate that the nanopore signal-to-noise ratio is significantly increased and the event signal becomes more stable and significant. Therefore, these attributes allow us to gain more insight into the assembly process of DNA nanostructures and we can use tetrahedral DNA nanostructure to develop an effective assay for identifying small molecules with the nanopipette.