Determination of azaspiracids in shellfish using liquid chromatography/tandem electrospray mass spectrometry.
Azaspiracid (AZA1), a recently discovered marine toxin, is responsible for the new human toxic syndrome, azaspiracid poisoning (AZP), which is caused by the consumption of contaminated shellfish. A new, sensitive liquid chromatography/mass spectrometry (LC/MS) method has been developed for the determination of AZA1 and its analogues, 8-methylazaspiracid (AZA2) and 22-demethylazaspiracid (AZA3). Separation of these toxins was achieved using reversed-phase LC and coupled, via an electrospray ionisation (ESI) source, to an ion-trap mass spectrometer. Spectra showed the protonated molecules, [M + H]+, and their major product ions, due to the sequential loss of two water molecules, [M + H - H2O]+, [M + H - 2H2O]+, in addition to fragment ions that are characteristic of these cyclic polyethers. A highly specific and sensitive LC/MS(3) analytical method was developed and, using shellfish extracts containing AZA1, the detection limit (S/N = 3) was 4 pg on-column, corresponding to 0.8 ng/mL. Using the protocol presented here, this is equivalent to 0.37 ng/g shellfish tissue and good linear calibrations were obtained for AZA1 in shellfish extracts (average r2 = 0.9988). Good reproducibility was achieved with % RSD values (N = 5) ranging from 1.5% (0.75 microg/mL) to 4.2% (0.05 microg/mL). An efficient procedure for the extraction of toxins from shellfish aided the development of a rapid protocol for the determination of the three predominant azaspiracids.
Furey
Ambrose
A
Ecotoxicology Research Unit, Chemistry Department, Cork Institute of Technology, Cork, Ireland.
Braña-Magdalena
Ana
A
Lehane
Mary
M
Moroney
Cian
C
James
Kevin J
KJ
Satake
Masayuki
M
Yasumoto
Takeshi
T
D000818:Animals; D002138:Calibration; D002853:Chromatography, Liquid; D004064:Digestive System / Q000737:chemistry; D005517:Foodborne Diseases; D007202:Indicators and Reagents; D008387:Marine Toxins / Q000032:analysis*; D008460:Meat / Q000032:analysis; D012758:Shellfish / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization; D013141:Spiro Compounds / Q000032:analysis*; D000095702:Polyether Toxins
D007202:Indicators and Reagents; D008387:Marine Toxins; D013141:Spiro Compounds; C406592:azaspiracid; D000095702:Polyether Toxins