There is a problem with the purification of a solution containing the following 4 dipeptides: Gly-His, Arg-Arg, Ala-Phe, and Asp-Val. Your superior has asked you to identify the following criteria using an anion exchange column and a hydrophobic column. Using an anion exchange column at pH 6, determine the order in which these four peptides will elute. From a hydrophobic column, identify which dipeptide would elute last.
Please include a detailed explanation for the answer.