Chapter 6
Advanced protein features
Page 6-26
MAN 0487
Interparticle distance
This tool is used to calculate the distance between the particles based on their
concentration and molecular weight. It also estimates the thickness of the
electrostatic layer based on protein charge and ionic strength.
The values are calculated according to the following formulae:
Dielectric constant
of the media
ε
r
is:
Hydrodynamic radius
estimated from molecular weight based on a globular
protein model:
The Debye length
is:
Separation distance
is:
where:
ε
o
= permittivity of free space (8.8542*10^-12 C/Vm)
κ
= inverse Debye length (1/nm)
N
A
= Avogadros' number (6.022*10^23 /mole)
K = Boltzmann's constant (1.38065*10^-23 m2kg/s2K)
T = temperature (K)
I = ionic strength (moles/L)
This assumes that the available solvent volume is equally distributed between all
particles, and that the particle is located in the centre of a cube that would represent
this solvent volume 'occupied' per particle. The interparticle distance, on average, is
then given by the edge length of the cube, representing the distance from the centre
of one cube to the centre of the neighbouring cube.
Mixture Viscosity
A simple tool that calculates the overall viscosity of a mixture of solutions based on
a volume weighted mean viscosity.
Summary of Contents for Zetasizer Nano Series
Page 2: ......
Page 3: ...Zetasizer Nano accessories guide MAN0487 Issue 1 1 April 2013...
Page 12: ...Chapter 1 Introduction and accessory range Page 1 6 MAN 0487...
Page 42: ...Chapter 2 General cells and cuvettes Page 2 30 MAN 0487...
Page 98: ...Chapter 5 Microrheology Page 5 20 MAN 0487...
Page 125: ......