During the webinar Automated two-step purification of antibody drug candidates, we collected a number of interesting questions on multistep processing. In this blog post, I have summarized questions related to principles of multistep processing and the case study presented by Erwin van Puijenbroek and Matthias Hermann, Scientists at F. Hoffman-La Roche.
Questions and answers
The first five questions are related to principles of multistep processing.
We do not always have one main peak. Often the impurity peaks approach target peak in size and the positions differ. How can we deal with this?
What if there are junk peaks that are numerous and sometimes larger than the wanted peak? Can you set the watch UV parameter to only kick in after a certain column volume to avoid larger junk peaks?
If you have a setup including protein A, anion exchange, and SEC steps, how do you adjust pH and perform buffer exchange in continuous mode?
The following questions are related to the case study presented during the webinar.
What is the biggest limitation for yield: the protein A column or the SEC column (or the desalting column)? How can you achieve amounts higher than the 500 µg shown in the first part of the presentation?
If you missed it, you can view the webinar on demand.
In a separate post, I have summarized questions related to methods for multistep processing and the example methods.