Question

Write 10 multiple choice questions with the answers on Ion exchange Chromatography

Answer 1

1.Ion exchange chromatography is based on the

A. electrostatic attraction
B. electrical mobility of ionic species
C. adsorption chromatography
D. partition chromatography

2.In anion exchange chromatography

a.The column contains negatively chareged beads where positively charged protein binds.

b.The column contains positively chareged beads  where negatively charged protein binds.

c.Column contains both negatively and positively charged beads where proteins bind depending on ther net charge.

d.all of these.

3.For an application where you require a sample of your target protein at high purity, what would be a good purification strategy? Assume that your starting point is E. coli cells in which the target protein fused to an affinity tag has been over-expressed.

a) Affinity chromatography (AC) followed by size exclusion chromatography (SEC)

b) AC only

c) AC followed by ion-exchange (IEX) followed by SEC

d) AC followed by IEX, followed by hydrophobic interaction (HIC) and then SEC

4.Which of these chromatography types are suitable as a "capture" step in the purification of non-tagged proteins?

a) SEC

b) Dialysis

c) IEX and HIC

d) Ammonium sulphate precipitation

5. Which chromatography relies on "strong and weak "that refers to the extent of variation of ionization with pH and not the strength of binding.

a.Ion exchange chromatography

b.Thin layer chromatography

c.Affinity chromatography

d.HPLC

6.In which chromatography .the pH of the mobile phase buffer must be between the pI (isoelectric point) or pKa (acid dissociation constant) of the charged molecule and the pKa of the charged group on the solid support.

a.Affinity chromatography

b.HPLC

c.column chromatography

d.Ion exchange chromatography

7. The anion used in polyacrylamide gel electrophoresis is

a.        Sodium dodecyl sulphate

b.        Socium citrate

c.        Sodium nitrate

d.        Sodium carbonate

8.The polymerization of polyacrylamide gel takes place due to

a.        Ammonium persulphate

b.        Riboflavin

c.        TEMED

d.        TEMED and ammonium persulfate both

9.Phosphate buffer has ………………. pKa values

a.        1

b.        2

c.        3

d.        4

10.Which chromatography uses a salt gradient or pH gradient?

a.ion exchange

b.Affinity

c.Gel electrophoresis

d.Gas chromatography