Chromatography: Introduction

1
Chromatography Introduction

• Dynamic separation process
• Based on inter-phase mass transfer
• Phases involved
• Stationary phase
• Mobile phase
• The stationary phase is generally arranged in the
  form of a packed bed
• The mobile phase flows through the stationary
  phase
• Substances to be separated are carried along
  through the packed bed by the mobile phase
• These substances selectively bind reversibly onto
  (or partition into) the stationary phase to
  different extents
• Based on this, these substances move through the
  column at different velocities

2
Chromatographic separation
Mobile phase
t0
t1
t2
t3
Stationary phase
3
Chromatography equipment
4
Chromatograms
Mobile phase
Mobile phase
Mobile phase
Mobile phase
Mobile phase
Sample
Peaks
Migrating bands
Concentration
Time
5
Chromatographic elution
Isocratic elution
A
Gradient elution
B
A
B
Gradients
B
Step
Linear
Non-linear
A
6
Chromatographic columns
Open tubular
Packed capillary
Packed bed
Membrane
Monolith
7
Separation mechanisms

• Adsorption
• Ion-exchange
• Reverse phase
• Hydrophobic interaction
• Size exclusion
• Supercritical fluid
• Affinity

8
Applications
Pharmaceuticals Fine chemicals Biotechnology En
vironmental analysis Foods and
nutraceuticals Water treatment Analysis of
chemicals Diagnostics Process control