Effect of Crown Ethers (YS-50)
Monovalent and divalent cations were analyzed using IC
 YS-50. 18-Crown 6- Ether will make a complex with cations, whose complex building depends on the kind of cations. Therefore, adding 18-Crown-6-Ether is able to control the elusion of cations and improve the separation of Na
+ and NH
4+. 

Sample : 10micro-L
 1. 
Li+ 2mg/L
2. 
Na+ 10mg/L
3. 
NH4+ 10mg/L
4. 
K+ 20mg/L
5. 
Mg2+ 10mg/L
6. 
Ca2+ 20mg/L
Column       : Shodex IC YS-50 (4.6mmID*125mm) 
Eluent       : 4mM Methanesulfonic acid + nmM 18-Crown 6-ether aq.
Flow rate    : 1.0mL/min
Detector     : Non-suppressed conductivity
Column temp. : 40deg-C