Question

Use the following structures of amino acids to answer the questions below. Note that the difference in the structures (the side chains) is highlighted by gray shading.

Answer 1

a) A student performed chromatography of the four amino acids and the results were shown in the chromatogram below. If an anion exchange column (column is positively charged) was used in a neutral buffer, assign each amino acid to the corresponding peak in the chromatogram.

Answer 2

b) Write 2 – 3 sentences to describe the interactions that will occur for each amino acid with the anion exchange column and its effect on column retention.

c) Write 2 – 3 sentences to describe how the results would differ if a cation exchange column (negatively charged column) were used.

Answer 3

The more the column interacts with the analytes (amino acids) the longer it will stay in the column and the longer time it will take to elute.

Coulomb's law state that opposites attract, thus the amino acid with the opposite charge to the column will interact more with the column than an amino acid of its same charge (like charges repulse).

http://www.lenntech.com/Data-sheets/Ion-Exchange-for-Dummies-RH.pdf
I would recommend checking out this document it seems to give a decent explanation of ion chromatography.

Answer 4

Also remember the more negative charges the less likely it will interact with the column, the more positive the more likely etc at least with a negative column

Answer 5

is the colomn the gray part of the amino acid

Answer 6

This is my guesses for answer a. a is aspartate b is threonine c is leucine and d is lysine. Am I correct