A new N-hydroxyethyliminodiacetic acid modified core-shell silica phase for chelation ion chromatography of alkaline earth, transition and rare earth elements.
Bare core-shell silica (1.7μm) has been modified with iminodiacetic acid functional groups via standard silane chemistry, forming a new N-hydroxyethyliminodiacetic acid (HEIDA) functionalised core-shell stationary phase. The column was applied in high-performance chelation ion chromatography and evaluated for the retention of alkaline earth, transition and heavy metal cations. The influence of nitric acid eluent concentration, addition of complexing agent dipicolinic acid, eluent pH and column temperature on the column performance was investigated. The efficiencies obtained for transition and heavy metal cations (and resultant separations) were comparable or better than those previously obtained for alternative fully porous silica based chelation stationary phases, and a similarly modified monolithic silica column, ranging from ∼15 to 56μm HETP. Increasing the ionic strength of the eluent with the addition of KNO3 (0.75M) and increasing the column temperature (70°C) facilitated the isocratic separation of a mixture of 14 lanthanides and yttrium in under 12min, with HETP averaging 18μm (7μm for Ce(III)).
Irish Separation Science Cluster (ISSC), National Centre for Sensor Research, Dublin City University, Dublin 9, Ireland.
Nicola
N
McGillicuddy
Ekaterina P
EP
Nesterenko
Pavel N
PN
Nesterenko
Elaine M
EM
Stack
Jesse O
JO
Omamogho
Jeremy D
JD
Glennon
Brett
B
Paull
D019342:Acetic Acid / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D009994:Osmolar Concentration
D002614:Chelating Agents; D008670:Metals; D019342:Acetic Acid
Core–shell silica particle, N-hydroxyethyliminodiacetic acid; High-performance chelation ion chromatography; Metal ions