![]() It involves separation of the PST after their derivatization and further fluorescence detection. The Lawrence method has been validated by the Association of Official Analytical Chemists (AOAC) through a collaborative trial and was adopted as the First Action HPLC-FLD Official Method. The most common chemical method uses a combination of HPLC with either pre- or post-column oxidation followed by fluorescence detection (FLD). A variety of modifications have led to improved separation and detection of the different congeners, including sample extraction, type of column, eluent composition and oxidation processes. Since then, many methods for toxin separation have been developed using both pre- and post-column oxidation with different types of columns. The basis of the HPLC method for PST analysis was established in the late 1970s, using post-column derivatization with a silica-based stationary phase. High performance liquid chromatography (HPLC) was one of the first analytical methods developed for STX detection, and it is routinely used. Secondly, we propose a modification of the method for the simultaneous analysis of PST and TTX, with some minor changes in the solvent gradient, although the detection limit for TTX does not allow its use nowadays for regulatory purposes.Īnalytical methods can be used to detect and quantify PST. diHCl kg −1 ) in oyster gonyautoxin 2 (GTX2) showed the highest limit of detection in oyster (0.0366 mg STX.diHCl kg −1 for each toxin) and dcSTX (0.0003 mg STX.diHCl kg −1), N-sulfocarbamoyl-gonyautoxins 2 and 3 (C1 and C2) in scallop (0.0001 mg STX.diHCl kg −1 for each toxin), decarbamoyl-saxitoxin (dcSTX) in clam (0.0003 mg STX.The results for all of the parameters studied are provided, and the detection limits for the majority of toxins were improved with regard to previous liquid chromatography methods: the lowest values were those for decarbamoyl-gonyautoxin 2 (dcGTX2) and gonyautoxin 2 (GTX2) in mussel (0.0001 mg saxitoxin (STX) The method was assayed in four shellfish matrices: mussel ( Mytillus galloprovincialis), clam ( Pecten maximus), scallop ( Ruditapes decussatus) and oyster ( Ostrea edulis). Firstly we describe the separation of 13 PST that belong to different groups, taking into account the side-chains of substituents, in one single run of less than 30 min with good reproducibility. The methods described here detail a new approach to eliminate different runs, by using a new porous graphitic carbon stationary phase. Furthermore, tetrodotoxin (TTX) was recently found in bivalves of northward locations in Europe due to climate change, so it is important to analyze it along with PST because their signs of toxicity are similar in the bioassay. This technique resulted in different methods that need more than one run to analyze the toxins. Paralytic shellfish toxins (PST) traditionally have been analyzed by liquid chromatography with either pre- or post-column derivatization and always with a silica-based stationary phase.
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