Fabrication of nanopores with ultrashort single-walled XXXX nanotubes inserted in a lipid bilayer.

@entity8316 @entity32428 @entity1172 @entity54926 @entity505
UNASSIGNED: We describe a protocol for the insertion of ultrashort single-walled @entity505 nanotubes (SWCNTs) to form nanopores in a Montal-Mueller lipid bilayer. The SWCNTs are designed to bind to a specific analyte of interest; binding will result in the reduction of current in single-channel recording experiments. The first stage of the PROCEDURE is to cut and separate the SWCNTs. We cut long, purified SWCNTs with sonication in concentrated @entity8316 / @entity32428 (3/1). Isolation of ultrashort SWCNTs is carried out by size-exclusion @entity1172 . The second stage is to insert these short SWCNTs into the lipid bilayer. This step requires a microinjection probe made from a glass capillary. The setup for protein nanopore research can be adopted for the single-channel recording experiments without any special treatment. The obtained current traces are of very high quality, showing stable baselines and little background noise. Example procedures are shown for investigating ion transport and DNA translocation through these SWCNT nanopores. This nanopore has potential applications in molecular sensing, nanopore DNA sequencing and early disease diagnosis. For example, we have selectively detected modified @entity54926 in single-stranded DNA (ssDNA), which may have implications in screening specific genomic DNA sequences. The protocol takes    15 d, including SWCNT purification, cutting and separation, as well as the formation of SWCNT nanopores for DNA analyses.
