03-08-2012, 04:29 PM
ION EXCHANGE CHROMATOGRAPHY
[attachment=30118]
Ion-Exchange Chromatography
• Ions are charged molecules
- cation positively charged ion
- anion negatively charged ion
• These ions do not separate smoothly under the traditional methods of the liquid
and mobile phases of chromatography
• Requires alteration methods of either the mobile phase or stationary phase are
required
Ion Exchange Chromatography Fractions
1.Bind protein to column in low
salt buffer
2.Wash column
3.Elute protein with
high salt buffer.
Cation exchange chromatography Protein
Protein samples are applied to
this column at low ionic strength,
and positively charged proteins
bind to the column support
Proteins are eluted using a gradient
of increasing ionic strength, where
counterions displace bound protein,
changing pH will also elute protein
Choice of functional groups on
distinct column supports allow a
range of affinities
[attachment=30118]
Ion-Exchange Chromatography
• Ions are charged molecules
- cation positively charged ion
- anion negatively charged ion
• These ions do not separate smoothly under the traditional methods of the liquid
and mobile phases of chromatography
• Requires alteration methods of either the mobile phase or stationary phase are
required
Ion Exchange Chromatography Fractions
1.Bind protein to column in low
salt buffer
2.Wash column
3.Elute protein with
high salt buffer.
Cation exchange chromatography Protein
Protein samples are applied to
this column at low ionic strength,
and positively charged proteins
bind to the column support
Proteins are eluted using a gradient
of increasing ionic strength, where
counterions displace bound protein,
changing pH will also elute protein
Choice of functional groups on
distinct column supports allow a
range of affinities