Ion chromatography for dummies

[orcicdejan]

We want to start analyzing anions by ion chromatography (we have Agilent's equipment). Any tips & tricks? How to prepare optimal mobile phase? Does anybody know what is composition of Agilent's 'mobile phase modifier'?
Thanks in advance!

[Alain]

You find it difficult to analyze Anions with a stainless steel system. PEEK would be best since eluents(mobile phases) are NaOH or Carbonate/Bicarbonate

[tom jupille]

Actually, Alain, anions can be analyzed quite well in SS systems (trust me on this, I used to do a lot of it! ).

orcicdejan, are you following a specific procedure from Agilent, or are you starting from scratch?

[Alain]

Good luck with that

[Yury Zelechonok]

If you can add ELS detector to your Agilent then many cations and anions can be analysed with simple technology discribed in
http://allsep.com/brochures/PrimesepIC_Rev3.pdf

[orcicdejan]

I'm using conditions recommended in Agilent's HP Anion Chromatography System User's Guide: mobile phase 810mL H2O + 50mL modifier + 140mL ACN + NaOH until pH=8,6, flow 1,5mL/min, oven 40"C, det UV 360/20nm vs 266/10nm. Column is Agilent-IC (Asahipak ODP-50 125x4mm). I've obtained good separation and sensitivity for F-, Cl-, SO4 2-, HPO4 2-, but signal for I- is too weak (for concentrations comparable to other ions, signal is ~10x weaker).

[Chris Pohl]

orcicdejan,

It looks like you are using indirect UV detection. In this mode you will not get good detection sensitivity for UV absorbing analytes such as iodide. Iodide is easy to detect via direct UV detection with a UV transparent eluent.