Dear All, I am having a consistency issue processing my SEC-MALS data. The sample is a 80KD protein which may form a dimer. The experiment I run a year ago shows a major peak at 11.4 ml (GE S200 column), which is calcuated to have a MW of 144kD. There is a minor peak at 10.0 ml. In an effort to make nice looking pictures, I rerun the experiement using the same setup (column, buffer, protein, speed) and again the major peak is at 11.4 ml but it is calcuated to have a MW of 80KD. I rerun the sample multiple times with the same result. I tried to reprocess the old data and the calcuated MW is still 144KD. I am puzzled about what I have done wrong and which data I should trust. Well, I am inclined to trust the later experiment because I took extra caution and had multiple data sets. However, I should be able to reprocess the old data to have a MW close to 80KD if I can find out what is wrong and correct the mistake, which I have not been able to. Any suggestions?
Zhen Zhang
