BACE Chromatography Techniques 2

Question 1

Which chromatography technique is most commonly used to purify His-tagged recombinant proteins?

Accepted Answer

Immobilized metal affinity chromatography (IMAC)

Answer

Size exclusion chromatography

Answer

Ion exchange chromatography

Answer

Reverse-phase HPLC

Question 2

In reverse-phase HPLC, the stationary phase is:

Accepted Answer

Nonpolar and hydrophobic

Answer

Highly polar and hydrophilic

Answer

Positively charged at neutral pH

Answer

A porous gel with defined pore size

Question 3

What reagent is typically used to elute a protein bound to a Ni-NTA IMAC column?

Accepted Answer

Imidazole at high concentration

Answer

High salt (e.g., 1 M NaCl)

Answer

Low pH buffer (pH 3.0)

Answer

Reducing agent such as DTT

Question 4

What does 'void volume' mean in the context of size exclusion chromatography?

Accepted Answer

The volume at which the largest excluded molecules elute

Answer

The volume of buffer needed to equilibrate the column

Answer

The total volume of liquid within the column

Answer

The sample volume that can be loaded safely

Question 5

Hydrophobic interaction chromatography (HIC) typically uses which condition to bind proteins to the resin?

Accepted Answer

High salt concentration

Answer

Low salt concentration

Answer

Low pH

Answer

High imidazole concentration

Question 6

Which instrument component in an HPLC system is responsible for detecting separated analytes as they exit the column?

Accepted Answer

Detector

Answer

Pump

Answer

Injector

Answer

Guard column

Question 7

In ion exchange chromatography, increasing the salt concentration in the elution buffer causes bound proteins to:

Accepted Answer

Elute from the resin

Answer

Bind more tightly to the resin

Answer

Precipitate inside the column

Answer

Migrate to a different zone on the column