Question

What would happen if we tried to preform Ion-Exchange Chromatography immediately after ammonium sulfate precipitation, rather than Gel Filtration Chromatography?

Answer 1

Gel filtration chromatography technique is commonly used prior to the ion exchange chromatography to achieve high quality proteins . But if we use ion exchange chromatography directly we will not get high quality protein. It may have some impurities . Because first, gel filtration is used to separate the proteins on the basis of their size then high purity is ensured by further separating them using ion exchange Method. But if we directly do ion exchange after ammonium sulphate precipitation, it might be possible that some same charged proteins of different sizes beloging to different domains get separated out simultaneously and will give us an impure yield.

But this doesn't happen if at first we apply gel filtration technique to separate them on the basis of their size which will ease the further process of ion exchange to give us a high quality yield.