Bio-Rad Bio-Scale™ Mini UNOsphere SUPrA™ Affinity Cartridges - Manual (Page 21)

Initial selectivity screening should be conducted with
a linear gradient. Knowledge of a monoclonal's
subclass may suggest a particular range of conditions,
but variation from one monoclonal to another is
sufficient to risk incomplete or no elution.
The choice of citrate for the low pH buffer is
predicated on the broad pH range achievable with
phosphate/citrate systems. If a higher pH range is
required, add boric acid to the binding buffer.
(Note: if CHT™ ceramic hydroxyapatite is used as
the subsequent polishing column, once scouting is
finished replace citrate with glycine or other
nonchelating salt for further process development.
Citrate buffers are incompatible with CHT.)
4.2 Scaling Up the Separation
For quick scale up, two or three cartridges of the
same type can be connected in series.
Backpressure will increase with cartridges in series,
so care should be taken to maintain pressures
≤45 psi.
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