Samples of mussels and flounders from the Baltic Sea were analysed for nodularin content
on two different LC–MS instruments (triple quadrupole and ion trap). The triple quadrupole
instrument was well suited for the quantitative analysis. The limit of detection in the selected
ion recording mode was 5 pg and in the multiple reactant monitoring mode 500 pg on
column for extracts of Nodularia spumigena. The fragmentation patterns of nodularin-R and
desmethylnodularin-R were recorded and shown to be similar to those of microcystins. LC …