Influence of different shellfish matrices on the separation of PSP toxins using a postcolumn oxidation liquid chromatography method

Abstract

The separation of PSP toxins using liquid chromatography with a post-column oxidation fluorescence detection method was performed with different matrices. The separation of PSP toxins depends on several factors, and it is crucial to take into account the presence of interfering matrix peaks to produce a good separation. The matrix peaks are not always the same, which is a significant issue when it comes to producing good, reliable results regarding resolution and toxicity information. Different real shellfish matrices (mussel, scallop, clam and oyster) were studied, and it was seen that the interference is not the same for each individual matrix. It also depends on the species, sampling location and the date of collection. It was proposed that separation should be accomplished taking into account the type of matrix, as well as the concentration of heptane sulfonate in both solvents, since the mobile phase varies regarding the matrix. Scallop and oyster matrices needed a decrease in the concentration of heptane sulfonate to separate GTX4 from matrix peaks, as well as dcGTX3 for oysters, with a concentration of 6.5 mM for solvent A and 6.25 mM for solvent B. For mussel and clam matrices, interfering peaks are not as large as they are in the other group, and the heptane sulfonate concentration was 8.25 mM for both solvents. Also, for scallops and oysters, matrix interferences depend not only on the sampling site but also on the date of collection as well as the species; for mussels and clams, differences are noted only when the sampling site varies.