title: New approach to the direct detection of known and new diarrhoeic shellfish toxins in mussels and phytoplankton by liquid chromatography-mass spectrometry.
abstract: A new approach using combined liquid chromatography-mass spectrometry (LC-MS) with ionspray ionization is proposed for the direct detection of known and new toxins in mussels and phytoplankton. A first stage reversed-phase, negative ion mode, selected ion monitoring (SIM) LC-MS analysis was performed in order to detect DSP toxins in the same chromatographic run with a total run time of 20 min. The toxins analysed included yessotoxin (YTX), okadaic acid (OA) and four of its analogues, dinophysistoxins (i.e. DTX-1, DTX-2, DTX-2B, DTX-2C), and pectenotoxins (PTXs), involving PTX-2, two PTX-2 secoacids (PTX-2SAs), PTX-2SA, 7-epi-PTX-2SA, and AC1, the three isomeric toxins structurally related to PTX-2 recently identified in Irish phytoplankton. Positive samples can, therefore, be analyzed through reversed-phase, positive ion mode SIM LC-MS, in order to perform complete chromatographic separations of the structurally related toxins within the OA and PTX groups. Detailed toxin profiles of a number of toxic phytoplankton and shellfish, from different marine areas, were easily obtained through the new approach. PTX-2SAs and AC1 were found in phytoplankton and shellfish from Ireland as well as in Italian shellfish. Moreover, for the first time there was evidence of the presence of PTX-2 in Irish phytoplankton. YTX was present in Italian shellfish. Four isomeric OA toxins were detected in samples from Ireland with OA, DTX-2 and DTX-2B present in shellfish, and OA, DTX-2 and DTX-2C in phytoplankton. In contrast, OA was the only toxin from this group to be detected in Italian mussels.
authors.affiliation: Laboratorio di Medicina Veterinaria, Istituto Superiore di Sanità, Rome, Italy. draisci@iss.it
authors.forename: R
authors.initials: R
authors.lastname: Draisci
authors.forename: L
authors.initials: L
authors.lastname: Palleschi
authors.forename: L
authors.initials: L
authors.lastname: Giannetti
authors.forename: L
authors.initials: L
authors.lastname: Lucentini
authors.forename: K J
authors.initials: KJ
authors.lastname: James
authors.forename: A G
authors.initials: AG
authors.lastname: Bishop
authors.forename: M
authors.initials: M
authors.lastname: Satake
authors.forename: T
authors.initials: T
authors.lastname: Yasumoto
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000379:methods*; D003967:Diarrhea / Q000139:chemically induced*; D008387:Marine Toxins / Q000032:analysis* / Q000633:toxicity; D013058:Mass Spectrometry / Q000379:methods*; D010839:Phytoplankton / Q000737:chemistry*
chemical_list: D008387:Marine Toxins