Bio-Rad Foresight™ Chromatography Columns, Prepacked - Manual (Page 7)

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Section 2
Theoretical Background
2.1 Batch Adsorption
Batch adsorption occurs when a liquid phase
containing an adsorbate (i.e., target biomolecule,
target impurity) comes in contact with a solid phase
(i.e., chromatographic media) in a vessel under
mixing. Batch adsorption is related to packed bed
adsorption primarily in two ways.
First, the mechanisms for mass transfer and ligand
adsorbate interaction are the same for both batch
adsorption and packed bed adsorption, meaning the
reaction is independent of the mode of operation.
This means that the adsorption data obtained using
plates can be used to describe the separation
occurring in a packed bed column.
Second, a packed bed is an array of batch
adsorption units connected in series with each unit
representing a theoretical plate. In the case of a
96-well filter plate, a single well is a batch adsorption
unit, hence a well is considered a theoretical plate.
2.2 Mass Balance
The mass balance of a solute between a solid and
a liquid phase in a batch system is represented as
follows:
Where C
0
and C are the initial and unbound liquid
phase concentrations, respectively. q represents the
bound solid phase concentration, V
0
represents the
initial liquid volume, and V represents the initial liquid
volume minus the liquid volume in the pores of the
media and the liquid held in the filter membrane.
Eq. 1