Quantitative Determination of Paralytic Shellfish Poisoning Toxins in Shellfish by Using Prechromatographic Oxidation and Liquid Chromatography with Fluorescence Detection

Abstract

The prechromatographic oxidation LC method developed by Lawrence [J. Assoc. Off. Anal. Chem. 74, 404–409(1991)] for the determination of paralytic shellfish poisoning (PSP) toxins has been tested for the quantitative determination of PSP toxins in shellfish. All aspects of the method were studied and modified as necessary to improve its performance for routine regulatory purposes. The chromatographic conditions were changed to shorten analysis time. The oxidation reaction was tested for repeatability and the influence of the s ample matrix on quantitation. An important part of the study was to quantitatively evaluate an ion exchange (-COOH) cleanup step using disposable solid-phase extraction cartridges that separated the PSP toxins into 3 distinct groups for quantitation, namely the C toxins, the GTX toxins, and the saxitoxin group. The cleanup step was very simple and used increasing concentrations of aqueous NaCl for elution of the toxins. The C toxins were not retained by the cartridges and thus were eluted unretained with water. The GTX toxins (GTX1 to GTX6 as well as dcGTX2 and dcGTX3) eluted from the cartridges with 0.05M NaCl while the saxitoxin group (saxitoxin, neosaxitoxin, and dcsaxitoxin) required 0.3M NaCl for elution. Each fraction was analyzed by LC after oxidation with periodate or peroxide. All of the compounds could be separated and quantitatively determined in spiked samples of mussels, clams, and oysters. The nonhydroxylated toxins could be quantitated at concentrations as low as about 0.02 μg/g (2 μg/100 g) of tissue while the hydroxylated toxins could be quantitated at concentrations as low as about 0.1 μg/g (10 μg/100 g). Average recoveries of the toxins through the complete cleanup procedure were 85%or greater for spiked extracts of oysters and clams and greater than 73%for mussels.

Large-Scale Sea Turtle Mortality Events in El Salvador Attributed to Paralytic Shellfish Toxin-Producing Algae Blooms

“…Samples from the 2013 event were analyzed for PST using HPLC with pre-column oxidation and fluorescence detection (Lawrence and Niedzwiadek, 2001) only. The HPLC system consisted of a Shimadzu (Tokyo, Japan) chromatograph equipped with an SCL-10A VP controller, LC-10 AD pump, SIL-10AF autosampler, CTO-10AS VP column oven, and RF-10A XL fluorescence detector.…”

“…The HPLC system consisted of a Shimadzu (Tokyo, Japan) chromatograph equipped with an SCL-10A VP controller, LC-10 AD pump, SIL-10AF autosampler, CTO-10AS VP column oven, and RF-10A XL fluorescence detector. Sample clean-up and PST separations were performed as described in Lawrence and Niedzwiadek (2001). Certified reference standards of STX, NEO, dcSTX, B1, GTX 1/4, GTX 2/3, dcGTX-2/3, and C1/2 (National Research Council, Canada) were used for instrument calibration.…”

Determination of Cell Abundances and Paralytic Shellfish Toxins in Cultures of the Dinoflagellate Gymnodinium catenatum by Fourier Transform Near Infrared Spectroscopy

“…The toxins converted into the correspondent fluorescent derivatives were determined using HPLC-FLD based on the precolumn oxidation method developed by [18]. The HPLC-FLD equipment consisted of a Hewlett-Packard/Agilent Model 1050 quaternary pump, Model 1100 in-line degasser, autosampler, column oven, and Model 1200 fluorescence detector.…”

Florecimientos algales nocivos producidos por Pyrodinium bahamense en Oaxaca, México (2009-2010)

“…Se aplicó el método de análisis de toxinas paralizantes en cromatografía líquida de alta resolución (HPLC) con detección de fluorescencia, oxidación precolumna y con un gradiente binario. 19,20 Se realizó una extracción ácida de las toxinas paralizantes a partir de 5 g de tejido de molusco fresco homogenizado en muestras compuestas por zona (Santiago Astata Est. 1, 2 y 3, y Puerto Escondido Est.…”