SENSITIVE HPLC FLUOROMETRIC AND HPLC MS DETERMINATION OF DIARRHETIC SHELLFISH POISONING (DSP)-TOXINS AS 4-BROMOMETHYL-7-METHOXYCOUMARIN ESTERS

Extracts containing the diarrhetic shellfish poisoning (DSP) toxins ok adaic acid (OA), dinophysistoxin-2 (DTX(2)), and dinophysistoxin-1 (DT X(1)) were purified on a silica gel cartridge and derivatized with 4-b romomethyl-7 methoxycoumarin (BrMmc). After pre-column derivatization the BrMmc derivatives of the DSP toxins were directly injected into an HPLC system, isocratically eluted, and quantified by fluorescence det ection. The signals of the esters showed good linearity in the fluores cence detector within the examined contamination range of 0.03 mg DSP/ kg to 2.5 mg DSP/kg. The detection limits for the DSP toxins as 7-Mmc esters were 0.04 ng (corresponding to 0.05 mg DSP/kg). The chromatogra phic conditions allow to couple the HPLC device with mass spectrometry . The method was tested with various mussel tissue samples.