Answer:
Step-by-step explanation:
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Ion exchange chromatography is necessary and is used for the separation of charged molecules. In this method or process, ionic solutes display reversible electrostatic interactions accompanied by the charged stationary phase, this usually comprises an insoluble matrix together with a covalently attached ion (ion exchanger). The solutes which are introduced in the column, perhaps(- ve) charged, (+ ve) charged, or neutral under a given condition.
So, the higher the charge density, the stronger the interaction.
pI of RNAP= 5.34
The pH of the experimental condition = 7.4
So, if pH is > pI of a solute, the solute gives H+ ion and converts to be (- ve) charged.
Thus, in this scenario (- ve) charged RNAP attaches to the (+ ve) charged ion exchanger. So, an anion exchanger (which is a basic ion exchanger) is imbibed in the separation of the anion in ion exchanger chromatography.
sample of such anion exchanger is DEAE - cellulose (Diethylaminomethyl).