Serum
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 2.5mM 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 : Serum, 10?L
1. Na+
2. NH4+
3. Ca2+
4. Mg2+
5. K+
Column : Shodex IC YK-421 (4.6mmI.D. x 125mm) Eluent : (A) 5mM Tartaric acid + 1mM Dipicolinic acid + 1.5g/L Boric acid aq. (B) 5mM Tartaric acid + 1mM Dipicolinic acid + 1.5g/L Boric acid + 2.5mM 18-Crown 6-ether aq. Flow rate : 1.0mL/min Detector : Non-suppressed conductivity Column temp. : 40°C