Changing pH can Effect These Parameters in CZE

When you change the pH of your CZE system, either the buffer or the conditions inside of your capillary, the following changes can be expected.

Electro osmotic Flow:

1. Lower pH extremes suppresses EOF.
2. Higher pH will speed the EOF.
3. Note: pH can effect the direction of EOF and migration of analytes.

Low pH can suppress protein to wall interaction and binding. This is especially true when operating at or below the pKa of your analyte.

1. The EOF can be suppressed or enhanced and therefore effect the migration time when pH is changed.
2. Migration time will normally increase with increasing pH. This can be overcome when using dynamic coating systems like CElixir.

1. Changing the pH can be used to sharpen your peaks. Find the optimal pH for your sample and sample matrix.
2. Changes in pH can be used in “zone focusing”.

When pH is increased so is electrophoretic mobility of analytes. This can be overcome when using dynamic coating systems like CElixir.