posted on 2015-12-17, 09:09authored byColin R. Crick, Jasmine Y. Y. Sze, Martin Rosillo-Lopez, Christoph G. Salzmann, Joshua B. Edel
The use of nanopore biosensors is
set to be extremely important in developing precise single molecule
detectors and providing highly sensitive advanced analysis of biological
molecules. The precise tailoring of nanopore size is a significant
step toward achieving this, as it would allow for a nanopore to be
tuned to a corresponding analyte. The work presented here details
a methodology for selectively opening nanopores in real-time. The
tunable nanopores on a quartz nanopipette platform are fabricated
using the electroetching of a graphene-based membrane constructed
from individual graphene nanoflakes (ø ∼30 nm). The device
design allows for in situ opening of the graphene membrane, from fully
closed to fully opened (ø ∼25 nm), a feature that has
yet to be reported in the literature. The translocation of DNA is
studied as the pore size is varied, allowing for subfeatures of DNA
to be detected with slower DNA translocations at smaller pore sizes,
and the ability to observe trends as the pore is opened. This approach
opens the door to creating a device that can be target to detect specific
analytes.