resist.total {breakage} | R Documentation |
Calculates the resistance of a pipette tip, as the sum of its internal conical resistance and external access resistance. Pipette geometry is specified in terms of length, tip radius and half-cone angle.
resist.total(r, l, theta, rho = 51)
r |
Pipette tip (inner) radius, in microns. |
l |
Pipette length, in microns. Note that resistance contribution falls of markedly away from the tip, so the exact length may not be crucially important. |
theta |
Pipette internal half-cone angle, in radians. |
rho |
Resistivity of the pipette filler medium, in ohm centimetres. The default value of 51 ohm cm corresponds to a 150 mM solution of KCl. |
The calculated total resistance, in ohms.
Matthew Caldwell
resist.access
, resist.cone
, resist.breakage
# total resistance for a 30 micron long pipette tip with a half-cone angle of 4 degrees # and a tip radius of 50nm, with a filler/bath resistivity of 64 ohm cm # converting result from ohms to megohms for readability resist.total(r=0.05, l=30, theta=4*pi/180, rho=64) * 1e-6