The low retentivity and few structural features of small monovalent organic acids typically dictates a weak eluent for their elution. In complex samples that also contains polyvalent organic acids, an initial isocratic section with weak hydroxide eluent can therefore be required before the gradient sets in. This example comes from an ion chromatography screening study at Diduco which tested several columns for analysis of some organic acids that were to be analysed in a pharmaceutical formulation.
