University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Marine -> shellfish

Citations 5

"Analysis Of Paralytic Shellfish Poisons By Capillary Electrophoresis"
J. Chromatogr. A 1991 Volume 542, Issue 2 Pages 483-501
P. Thibault, S. Pleasance and M. V. Laycock

Abstract: Underivatized saxitoxin (I) and neosaxitoxin (II) were separated by capillary electrophoresis on a fused-silica capillary column (90 cm x 50 µm) with either sodium citrate buffer (20 mM, pH 2) or acetic acid (0.1M, pH 2.9); detection was at 200 nm. Sample introduction was performed using either hydrodynamic or electrokinetic injections. Identification of the electrophoretic peaks was confirmed by MS using ionspray ionization and by HPLC with fluorescence detection. The limits of detection were 15 and 18 pg for I and II, respectively; improvements in sensitivity are likely to be achieved using pre- or post-column fluorescent derivatization. Results for dinoflagellates and scallops are presented and are reproducible in terms of both migration times and sensitivity, comparing well with existing techniques.
Saxitoxin Neosaxitoxin HPLC Electrophoresis Fluorescence Mass spectrometry Buffer Column Silica

"Application Of HPLC For The Determination Of Paralytic Shellfish Poisoning Toxins In Shellfish"
J. Food Sci. 1985 Volume 50, Issue 1 Pages 26-29

Abstract: Shellfish samples were extracted and assayed for toxicity by the standard bioassay method (AOAC, 1980). A portion of the supernatant solution after sample extraction was treated with aqueous 40% trichloroacetic acid, pH 4.5, at 4°C overnight. The protein ppt. was separated by centrifugation and, after dilution and filtering through a Millipore filter, samples of supernatant solution were subjected to HPLC on a PRP-1 column with a mobile phase containing hexane- and heptane-sulfonic acids as ion-pair reagents, NH4+ as co-cation and methanol. Toxins were detected by fluorimetry after post-column derivatization with periodic acid. There were apparently no systematic differences between the bioassay and HPLC methods, but HPLC showed much greater sensitivity (detection limit 0.006 to 0.15 µM compared with 0.4 to 59 µM for the bioassay) and permitted determination of the levels of individual paralytic shellfish poisoning toxins.
Toxins HPLC Fluorescence Post-column derivatization

"Ion-spray Mass Spectrometry Of Marine Neurotoxins"
Rapid Commun. Mass Spectrom. 1989 Volume 3, Issue 5 Pages 145-150
Michael A. Quilliam, Bruce A. Thomson, George J. Scott, K. W. Michael Siu

Abstract: Ion-spray mass spectrometry was investigated for the analysis of three marine neurotoxins: domoic acid, saxitoxin and tetrodotoxin. All three compounds gave positive-ion spectra with abundant ions of protonated molecules and no significant fragmentation. Domoic acid gave a negative-ion spectrum with a strong [M-H]- ion. Tandem mass spectrometry provided useful fragment-ion spectra for all compounds. Detection limits for flow injection analyzes with selected-ion monitoring were determined to be 30 pg for saxitoxin, 100 pg for domoic acid and 200 pg for tetrodotoxin. Combining liquid chromatography with ion-spray mass spectrometry allowed the determination of domoic acid and some of its isomers in toxic shellfish tissue extracts.
Saxitoxin Domoic acid Tetrodotoxin LC Mass spectrometry Sample preparation Detection limit

"Ion-spray Mass Spectrometry Of Marine Toxins. 3. Analysis Of Paralytic Shellfish Poisoning Toxins By Flow Injection Analysis, Liquid Chromatography - Mass Spectrometry And Capillary Electrophoresis - Mass Spectrometry"
Rapid Commun. Mass Spectrom. 1992 Volume 6, Issue 1 Pages 14-24
S. Pleasance, S. W. Ayer, M. V. Laycock, P. Thibault

Abstract: The cited techniques were used to monitor the purification of saxitoxin, the parent compound in the family of toxins that cause paralytic shellfish poisoning (PSP). The results obtained by flow injection analysis are compared with those by HPLC with post-column oxidation and fluorescence detection. The coupling of LC and capillary electrophoresis with ion-spray MS in the separation of mixtures of PSP toxins and tetrodotoxin is described. Tandem MS gave structural information, and it is shown that isomeric PSP toxins can be distinguished both chromatographically and by MS. (For Part II see Anal. Abstr., 1991, 53, 9H90). Ion-spray mass spectrometry has been used to monitor the purifn. of saxitoxin, the parent compound in the family of toxins responsible for paralytic shellfish poisoning (PSP), from a strain of the dinoflagellate Alexandrium excavatum. Quant. results obtained by flow injection analysis are compared to those obtained by high performance liquid chromatography with post-column oxidation and fluorescence detection. The coupling of liquid chromatography and capillary electrophoresis with ion-spray mass spectrometry is described for the separation of mixtures of PSP toxins and the highly potent pufferfish toxin tetrodotoxin. Tandem mass spectrometry is used to provide the structural information, and the ability to distinguish isomeric PSP toxins both chromatography and mass spectrometrically is demonstrated.
Saxitoxin Mass spectrometry Method comparison

"Direct Identification Of Yessotoxin In Shellfish By Liquid Chromatography Coupled With Mass Spectrometry And Tandem Mass Spectrometry"
Rapid Commun. Mass Spectrom. 1998 Volume 12, Issue 19 Pages 1291-1296
Rosa Draisci *, Luigi Giannetti, Luca Lucentini, Emanuele Ferretti, Luca Palleschi, Camilla Marchiafava

Abstract: A new method for the direct identification of yessotoxin (YTX), a polyether compound belonging to the diarrheic shellfish poisoning (DSP) toxins, using liquid chromatography coupled with mass spectrometry and tandem mass spectrometry (LC/MS and LC/MS/MS) is reported. Full-scan ion-spray mass spectra of YTX, as acquired in single MS negative ion mode by flow injection analysis (FIA), showed the most intense ion at m/z 1141, assigned to the [M-2Na+H]-, the ion at m/z 1163, assigned to the [M-Na]- and a signal at m/z 1185, due to the deprotonated mol. [M-H]- of the analyte taken here to be the disodium salt. Collision induced dissociation of the precursor ion at m/z 1141, as obtained by FIA negative tandem mass spectrometry experiments, showed the most intense fragment ions in the higher mass region, at m/z 1061, m/z 924, m/z 855, m/z 713, which are characteristic of the structure of the analyte. Ion-spray reversed phase LC/MS and LC/MS/MS was performed by isocratic elution at 30 µL/min, with a mobile phase of acetonitrile-ammonium acetate 4 mM, 80:20 (v/v), using a 1.0 mm i.d. C18 column. The detection of YTX in Italian shellfish samples collected in 1997 from the Adriatic sea was successfully carried out using this method, permitting demonstration of a false negative result obtained by the official mouse bioassay during routine control monitoring.
Yessotoxin HPLC Mass spectrometry Method comparison