Monovalent and Divalent Cation Standards (3) (Dipicolinic Acid + Crown Ether Eluent)

The problems in the anaysis using IC YK-421 is that the analysis of very small amount of NH4+ in a sample which contains large amount of Na+ is difficult. Addition of 1.5mM 18-Crown 6-ether in 5mM Tartaric acid + 1mM Dipicolinic acid + 1.5g/L Boric acid eluent can solve the problem. Addition of crown 6-ether can adjust the elution volume of the cations. Especially, the elution volume of K+ is largely affected by the additon and elute after Mg2+.


Sample :
1. Li+
2. Na+
3. NH4+
4. Ca2+
5. Mg2+
6. K+

Column       : Shodex IC YK-421 (4.6mmID*125mm)
Eluent       : 5mM Tartaric acid + 1mM Dipicolinic acid + 1.5g/L Boric acid + 1.5mM 18-Crown 6-ether aq.
Flow rate    : 1.0mL/min
Detector     : Non-suppressed coductivity
Column temp. : 40deg-C