High Sensitive Detection of Cations

Monovalent and divalent cation standards were analyzed using IC YK-421. Using a highly sensitive conductivity detector, cations whose concentrations are micro-g/L(=ppb) level can be detected. Minimum detection levels are shown in the table(S/N=3). The figures in parentheses are minimum concentrations when 100 micro-L of sample is injected.

Sample	Minimum detection levels (S/N=3)
1. Li+	-	-
2. Na+	0.15ng	(1.5 micro-g/L)
3. NH4+	0.30ng	( 3 micro-g/L)
4. K+	0.60ng	( 6 micro-g/L)
5. Ca2+	0.20ng	( 2 micro-g/L)
6. Mg2+	0.20ng	( 2 micro-g/L)
( ) : minimum concentrations when 100 micro-L of sample is injected.

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