Studies of Ionic Current
Rectification Using Polyethyleneimines
Coated Glass Nanopipettes
- Publication date
- Publisher
Abstract
The modification of glass nanopipettes with polyethyleneimines
(PEIs) has been successfully achieved by a relatively simple method,
and the smallest tip opening is around 3 nm. Thus, in a much wider
range of glass pipettes with radii from several nanometers to a few
micrometers, the ion current rectification (ICR) phenomenon has been
observed. The influences of different KCl concentrations, pH values,
and tip radii on the ICR are investigated in detail. The sizes of
PEIs have been determined by dynamic light scattering, and the effect
of the sizes of PEIs for the modification, especially for a few nanometer-pipettes
in radii, is also discussed. These findings systemically confirm and
complement the theoretical model, and provide a platform
for possible selectively molecular detection and mimic biological
ion channels