HW#1 BE 131/231
1. Lets look at conical nanopores. A right circular cone has a cross-section that is an
isosceles triangle, meaning that the radius of the cone is a linear function of the
distance down the axis:
r
x
A truncated cone is a cone which doesnt

Creating nanopores from the
bottom up
Creation of inorganic nanopores
starting from small structures
Silica nanotubes
Nanotemplates
Si nanowires were created by CVD
These were coated with SiO2 through high temperature oxidation
of the Si in O2 , resulti

HW#2 BE 131/231
1. You have a solution of .01M, .1M, and 1M KCl. Look up the conductivity of this
solution.
a. Calculate the resistance of a cylindrical channel filled with this fluid 50 um
long and 20 um in diameter. Repeat for a channel .5 um long and .

Scaling down pore size: from
cells to molecules
Decreasing the channel size
Notice that the signal height
does not change as we
change the channel width
(this should be obvious why)
But the fractional signal
does:
We can see that as the
particle size g

BE 131/231
Nanopore Sensing
Thought experiment
Imagine you have a current-carrying wire:
A nick in it will increase the resistance of the
wire:
Thought experiment, 2
This is the same for an ionic current flowing
through an electrolyte filling a pipe
A