<prompt> The ability of amino acidsproteins to behave like zwitterions forms the basis for separating them using the following techniqueGel filtration chromatographyIon exchange chromatographyIsoelectric focusingMass spectrometry  <response>: Isoelectric focusing is based on the isoelectric pH pH at which a molecule carries no net charge. pH gradients created in the gel using polyampholytes. As there is no net charge, molecule stops moving during electrophoresis if they encounter their pI. 