We can open our knob and collect that protein in a test tube. And likewise, we can wait longer period of time, and then we can collect protein number two in our second test tube. Now, the problem with protein One is we have to wait a very, very long time. And so, to speed up the process, we can basically look at diagram E. And in diagram E, what we do is we essentially pour a salt solution into our mixture. And what the salt solution does is, so the salt solution, for example, can contain sodium chloride ions. And what happens is the sodium and the chloride ions dissociate in our solution, and those positively charged sodium ions will begin to interact with these negatively charged beads.