RE: New SARS- CoV-2 variant29 Oct 2020 15:45
CO, not my area but I think it has a 'proof reading' complex that corrects sequence replication mistakes and so has a lower mutation rate than some viruses.
I am sure the initial screen of the Affimers would have been just to find a pair of specific binders.
There will however, be some binding site of the S1 which are not variable, they have now had quite a bit of time now to select for ones that bind these regions, (it may be the ones they have already do), provided that they can get the specificity then these would be quite durable.