title: A study of ten toxins associated with paralytic shellfish poison using prechromatographic oxidation and liquid chromatography with fluorescence detection.
abstract: Ten paralytic shellfish toxins [saxitoxin, neosaxitoxin, B-1, B-2, gonyautoxin 1, 2, and 3 (i.e., GTX-1, GTX-2, and GTX-3), C-1, C-2, and C-3] were oxidized at room temperature under mildly basic conditions with hydrogen peroxide or periodic acid. The products were then analyzed by liquid chromatography (LC). The N-1-hydroxylated toxins (neosaxitoxin, B-2, GTX-1, and C-3) formed fluorescent products after periodate oxidation at ca pH 8.7, but did not form fluorescent derivatives with peroxide oxidation. The non-N-1-hydroxylated toxins (saxitoxin, B-1, GTX-2, GTX-3, C-1, and C-2) formed highly fluorescent derivatives with both peroxide and periodate oxidations. Individual toxins produced mainly single fluorescent peaks by reverse-phase LC. However, all GTX toxins eluted with the same retention time. Also, C-1 and C-2 eluted together, as did neosaxitoxin and B-2. The non-N-1-hydroxylated toxins could be detected in quantities as low as 20-50 pg/injection, while the N-1-hydroxy analogues could be detected at levels as low as 100-500 pg/injection. UV absorption and fluorescence emission spectra were similar for the oxidation products of all toxins examined (max. 333 +/- 2 nm absorption, 389 +/- 4 nm fluorescence emission).
authors.affiliation: Health Protection Branch, Bureau of Chemical Safety, Ottawa, Ontario, Canada.
authors.forename: J F
authors.initials: JF
authors.lastname: Lawrence
authors.forename: C
authors.initials: C
authors.lastname: Ménard
authors.forename: C F
authors.initials: CF
authors.lastname: Charbonneau
authors.forename: S
authors.initials: S
authors.lastname: Hall
mesh_terms: D000818:Animals; D001681:Biological Assay; D002853:Chromatography, Liquid / Q000379:methods; D006861:Hydrogen Peroxide; D008387:Marine Toxins / Q000032:analysis*; D051379:Mice; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010504:Periodic Acid; D012758:Shellfish / Q000032:analysis*; D013050:Spectrometry, Fluorescence; D013997:Time Factors
chemical_list: D008387:Marine Toxins; D010504:Periodic Acid; D006861:Hydrogen Peroxide