Influence of Sample Treatment. Because of the complexing
ability of the PDCA the analytes must be in a free available
form, only weakly complexed, or hydrated to be properly
chromatographed (2). The sample treatments must therefore
liberate the metals from their matrices to facilitate the PDCA
complexing. Unexpectedly, when Met Pac PDCA eluent and
PAR postcolumn reagent from Dionex were used, a much lower
response for nickel was observed.
The acidification treatment is a fast and simple preparation,
but only for hydrated and weakly complexed soluble minerals