Effect of pH on Retention Time (NI-424)

When using IC NI-424 and the pH of the eluent is increased on the alkaline side, overall elution shortens. At a pH of 4.5 or higher, separation of F- and H2PO4- is difficult.

Sample : 30micro-L
1. H2PO4-
2. F-
3. Cl-
4. NO3-
5. SO42-
6. I-
7. SCN-

Column       : Shodex IC NI-424 (4.6mmID*100mm)
Eluent       : 8mM 4-Hydroxybenzoic acid + 2mM Phenylboronic acid + 0.005mM CyDTA(pH adjusted with Bis-Tris)
Flow rate    : 1.0mL/min
Detector     : Non-suppressed conductivity
Column temp. : 40deg-C