Now, we're not going to focus too much on each one of these steps because we spoke about these in detail in previous lectures. We're simply going to show you the fact that we can combine these two techniques to basically create a more effective method. So, in the first step, we take our crude mixture of proteins found in the following beaker, and we expose it to isoelectric focusing. So remember, in isoelectric focusing, we essentially have this gel. And that gel contains a PH gradient. So on one side, we have a low PH acidic, and that's when we have many of these positively charged H ions.