High-performance liquid chromatographic separation of microcystins and nodularin, cyanobacterial peptide toxins, on C-18 and amide C-16 sorbents

Four C-18 columns and a novel amide C-16 column were assessed in the HPLC s eparation of eight microcystins and nodularin-R. Gradient mobile phases of acetonitrile combined with trifluoroacetic acid, formic acid or ammonium ac etate were compared. Special attention was paid to the resolution of four p ossible coeluting microcystin pairs. Generally speaking, the acidic mobile phases were superior to the ammonium acetate-based mobile phase in terms of resolution and selectivity. The amide C-16 column had the best overall per formance and unique selectivity properties. (C) 2001 Elsevier Science B.V. All rights reserved.