Abstract:
:Protein dynamic binding capacities on ion exchange resins are typically expected to decrease with increasing conductivity and decreasing protein charge. There are, however, conditions where capacity increases with increasing conductivity and decreasing protein charge. Capacity measurements on two different commercial ion exchange resins with three different monoclonal antibodies at various pH and conductivities exhibited two domains. In the first domain, the capacity unexpectedly increased with increasing conductivity and decreasing protein charge. The second domain exhibited traditional behavior. A mechanism to explain the first domain is postulated; proteins initially bind to the outer pore regions and electrostatically hinder subsequent protein transport. Such a mechanism is supported by protein capacity and confocal microscopy studies whose results suggest how knowledge of the two types of IEX behavior can be leveraged in optimizing resins and processes.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Harinarayan C,Mueller J,Ljunglöf A,Fahrner R,Van Alstine J,van Reis Rdoi
10.1002/bit.21080subject
Has Abstractpub_date
2006-12-05 00:00:00pages
775-87issue
5eissn
0006-3592issn
1097-0290journal_volume
95pub_type
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