Narrowbore high performance liquid chromatography (HPLC) was scaled down stepwise to capillary HPLC employing 2.1, 1 and 0.32 mm id separation columns. Provided that each column was operated at optimum chromatographic conditions (eluent velocity, injection volume) and provided that system connection (tubing, unions) was optimal, the influence of different HPLC-ICP-MS interfaces on extra column dispersion could be investigated. Several pneumatic nebulizers i.e. PFA-ST, MCN6000, AriMist, direct injection high efficiency nebulizer (DIHEN), CEI-100 and a costume made PFA005 nebulizer were tested. It could be shown that the contribution to extra column dispersion is minimal for the DIHEN interface. As a major advantage most of the microbore and capillary hyphenations were not prone to signal suppression due to organic solvents. The 1 mm id microbore set-up employing flow rates of 60 μL min-1 offered the best compromise in terms of sensitivity, peak dispersion, resolution, peak asymmetry and compatibility with organic solvent.
ASJC Scopus subject areas
- Analytical Chemistry