Use gel filtration, I think that G-10 is OK to recover all proteins including lower size peptides

You can use small desalting column that can be use on tabletop centrifuge really quick and usefull.

If you have a large sample volume using gel filtration and desalting columns for desalting would require you to concentrate the sample unless you have the time to do 50+ runs. Concentrating crude protein extracts also takes very long time plus you would have to use a small MWCO (molecular weight cut off). What do you plan to do with your sample? Ion exchange chromatography? If yes I would recommend to heavy dilute your sample with your buffer A and let it run over the column. Your protein(s) bind to the resin and you can run a gradient if desired.

G-10/desalting column are good options, you can run fairly large volumes on G-10 columns in minutes and automate the operation (e.g. with AKTA) to repeat it as many times as you need to desalt even 100s ml in a day.

As an alternative you should consider tangential flow filtration for uninterrupted concentration and buffer exchange (or the other way around if more convenient)

In our laboratory we use Amicon centrifugal desalting columns from Merck. It comes with various cut-off points so you get to choose the desired size for your protein. Percentage recovery using the column is acceptable, and the overall process is quick and fairly simple.

Another option is ultrafiltration, with several washes of the concentrated sample with your buffer of choice. But you need an ultrafiltration cartridge, a filter and a connection to compressed inert gas (nitrogen). It might be helpful to know the volume you wish to desalt and the next step you plan to do to be more helpful.

Dear All

Francisco Solano, Bertrand Didier Raynal, Cornelia Virus, Carlo Zambonelli , Allan Wee Ren Ng, and Marko Dolinar

Thanks for your valuable response, it really helpful for me in my work.

Regards

Sehroon