National Research Council of Canada. NRC Institute for Marine Biosciences
An improved liq. chromatog./mass spectrometric (LC/MS) method utilizing gradient elution and ion-spray ionization is described for the sensitive detn. of okadaic acid and dinophysistoxin-1, the principal toxins implicated in cases of diarrhetic shellfish poisoning. The method was used to confirm the presence of both toxins, together with a recently identified isomer of okadaic acid, dinophysistoxin-2, in various samples of cultivated blue mussels (Mytilus edulis) from Canadian and European waters. The method provided a mass detection limit of 0.4 ng for each toxin, thus allowing detection of 40 ng per g of whole mussel tissue (or approx. 10 ng/g if only the digestive glands were used in the assay). Quant. results obtained by LC/MS were in good agreement with those obtained by derivatization and high-performance liq. chromatog. with fluorescence detection.
Rapid Communications in Mass Spectrometry6, no. 2: 121–127.