9
Downstream
thirty seven
Downstream 36 investigated how well MabSelectTM, a protein A
based affinity medium, withstands repetitive cleaning-in-place
under real conditions and found the results impressive. This
issue examines the transfer of a packing method for MabSelect
to a ChromaflowTM 600 production column. Once again,
MabSelect demonstrates that it meets the demands of
monoclonal antibody manufacturers.
Packing MabSelect
in a Chromaflow 600 column
Packing MabSelect in
Chromaflow is fast and
convenient. The method
scales-up well from the
400 id column, resulting
in excellent bed efficiency
and stability.
G
ood column packing, essential for any
chromatographic process, is a critical parameter in
large-scale commercial manufacture. A bed packed
too densely may crack, which can lead to channeling and
early break-through. A bed packed too loosely can further
compress causing a liquid gap where mixing can occur.
Proper packing will eliminate such concerns and ensure a
stable bed that performs according to expectations over
many processing cycles.
Meeting industry's processing needs
MabSelect is designed to meet the needs of commercial
manufacture. Based on a highly rigid and very porous agarose
matrix, MabSelect provides high dynamic binding capacity at
high fluid velocities, allowing large volumes of cell culture
supernatant to be processed in very
short times. With this attribute, plus
its ability to withstand long-term
cleaning-in-place, MabSelect gives
commercial manufacturers a highly
productive purification tool. At fluid
velocities of 500 cm/h and a packed
bed height of 20 cm, the dynamic
capacity of MabSelect is typically 30
mg polyclonal antibody/ml medium.
Fermenter volumes of 10 000 liters
or more can be processed in a single
working day (see Downstream 33).
Interest in large-scale operations is thus considerable, and an
easy, robust and scalable column packing method is therefore
needed. We describe and test such a method for packing
MabSelect in a Chromaflow 600 column (i.d. 60 cm).
Transfer to Chromaflow 600
Previous packing studies in other columns, including BPGTM
300 and Chromaflow 400, have shown the good pressure/
flow properties of MabSelect (Figure 1).
The method used for Chromaflow 600 is based on a
standard Chromaflow procedure, i.e. via nozzles in the top
and bottom end-pieces, with the lid and adaptor in place. In
this case, the adaptor was set to give a packed bed height of
20 cm, the optimum for MabSelect, though it can be packed
to other heights. The medium used was taken from a routine
production batch during analytical
specification.
The packing flow velocity was about
1500 cm/h (70.5 l/min) and at a final
bed height of 20 cm, the calculated
volume of MabSelect was 56.5 liters.
Since the packing flow rate was very
high, the column filled in about
2 minutes. The complete packing
procedure is simple, fast and efficient,
taking no more than 30 minutes
and requiring just one person.
0
200
400
600
800
1000
1200
1400
0
0,05
0,1
0,15
0,2
0,25
0,3
0,35
0,4
Pressure [MPa]
Liquid velocity [cm/h]
BPG 100
FineLINE 200
BPG 300
Chromaflow 400
Fig. 1. Pressure/flow rate curves for MabSelect in other
columns.
