Bio-Rad Foresight™ Chromatography Columns, Prepacked - Manual (Page 17)

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3.2 Types of Studies
3.2.1 Screening
To utilize the full potential of HT experimentation,
statistical DoE is recommended. DoE identifies
the experimental variables with the most
significant impact on the experiment’s output(s)
in relatively few experiments. Examples of
experimental variables include, but are not limited
to, pH, conductivity/ionic strength, salt type,
additives, and sample protein concentration.
To guarantee a desired load for the DoE work,
a preliminary uptake kinetic experiment is
recommended. This experiment provides the
contact time required to achieve a given load
and elucidates whether enough protein feed
concentration was provided. If time and sample
quantity allow, an additional isotherm experiment
is recommended.
This experiment yields the range of feed
concentration engulfing the plateau region of
the isotherm, where the capacity is practically
insensitive to changes in the feed concentration.
Note: A binding kinetic experiment (uptake curve)
provides the incubation time required to achieve
a desired load. Uptake data in juxtaposition with
isotherm data provide a reliable way to determine
the range of initial feed concentrations that leads
to media saturation.
Screening studies can be used to find conditions
that: (a) maximize load (binding of a target
protein), (b) lead to flowthrough of the target or
its similar impurities, and (c) lead to optimum
levels of yield and purity. Furthermore, screening
studies might also be used to scout for optimal
cleaning conditions.