Yesterday, I visited my old chair in Erlangen and we had a discussion about the effect of temperature on the binding strength.
Here are measurements of an experiment at three different temperatures, using a (not so monodisperse) PEG 1400 standard :
The question is now, how would we go about modelling this effect in CADET? Especially, if there were to be gradients during a simulation. I remember having discussed the general topic with some of you and if I recall correctly, there were two general approaches:
- Using external functions.
- Modelling temperature as a pseudo-component which influences the binding strength.
However, I’ve never implemented any of those and if there were some examples I could use as a template, I’d be grateful. Or maybe there is even a more elegant way to model this.
Other than that I think it would be a cool demonstration of the advanced features of CADET, especially because there is experimental data to compare it to.
I would be very happy to see such examples in the CADET model library.
Correct, you can use these two approaches. The extrenal function approach alters the parameters of an existing binding model. I believe the pseudo-component approach will require to implement a customized binding model in most application cases.
@s.leweke has provided Matthias Franzreb at KIT with a customized code for this. Maybe that can be revoked. There also has been data, but we never saw a paper that came out of this effort.
There is not much litereature on thermoresponsive chromatography, but Shamsul Qumar and Andreas Seidel-Morgenstern also have published a few papers in this direction.
Actually, that wasn’t a customized version, but simply the publicly available mainstream version. So the functionality is already implemented (and generalized since we can now use multiple external functions).
Unfortunately, I don’t have an example from Matthias Franzreb / Benedikt Ketterer. The Matlab interface has some (completely random) example on how to use external functions.
As @lieres mentioned, there are some papers on mechanistic modeling, which boil down to a temperature component and modified binding models.
A warm welcome to @malvina.supper who is working on this topic in Erlangen.
@s.leweke thanks, I will look into the Matlab examples for external functions.
Thank you for adding me to this exclusive group The experiments above (RPLC) were done using isocratic conditions last week and we are planing to continue to investigate temperature effects soon. As I just started one month ago I am not entirely sure where things are heading. One note: this effect (of prolonged retention time with increasing temperature) only refers to PEG, usually a reversed effect is expected.