title: Measurement of paralytic shellfish toxins in molluscan extracts: comparison of the microtitre plate saxiphilin and sodium channel radioreceptor assays with mouse bioassay, HPLC analysis and a commercially available cell culture assay.
abstract: This study compared five methods of measuring paralytic shellfish toxins (PSTs) including the long-used mouse lethality bioassay, a commercially available cell culture test (MIST Quantification kit), HPLC analysis, and two newly developed radioreceptor assays utilizing mammalian sodium channels and saxiphilin. Methods were challenged with toxic shellfish extracts prepared according to the AOAC official method. The best correlations between predicted toxicity values being 0.9 or better, were those between HPLC analysis when compared with both radioreceptor assays and the mouse lethality bioassay, as well as that between the saxiphilin and the sodium channel radioreceptor assays. In all cases, statistically significant correlations existed between the toxicity measurements of the same extracts. The ratios between some methods were not unitary as measured by the slopes of the regression lines used for correlation analyses. HPLC analysis predicted more toxicity than all of the bioassays. The saxiphilin assay underestimated toxicity relative to the mouse bioassay, the MIST kit determinations and the sodium channel assay. The sodium channel assay predicted there to be less toxicity than the mouse bioassay and the MIST kit. Of all of the techniques used, the MIST kit correlation with the mouse bioassay was nearest to one. Each method possesses differentt virtues and it may be that a multi-method approach would harness the benefits of each method for various aspects of a shellfish testing regime.
authors.affiliation: Australian Institute of Marine Science, PMB 3, Townsville MC, Qld. L.Llewellyn@aims.gov.au
authors.forename: L E
authors.initials: LE
authors.lastname: Llewellyn
authors.forename: J
authors.initials: J
authors.lastname: Doyle
authors.forename: J
authors.initials: J
authors.lastname: Jellett
authors.forename: R
authors.initials: R
authors.lastname: Barrett
authors.forename: C
authors.initials: C
authors.lastname: Alison
authors.forename: C
authors.initials: C
authors.lastname: Bentz
authors.forename: M
authors.initials: M
authors.lastname: Quilliam
mesh_terms: D029845:Amphibian Proteins; D000818:Animals; D001681:Biological Assay / Q000379:methods / Q000592:standards; D002352:Carrier Proteins; D018929:Cell Culture Techniques / Q000379:methods / Q000592:standards; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D008387:Marine Toxins / Q000032:analysis*; D051379:Mice; D008974:Mollusca; D011869:Radioligand Assay / Q000379:methods / Q000592:standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012758:Shellfish; D015222:Sodium Channels; D017186:Titrimetry / Q000379:methods / Q000592:standards
chemical_list: D029845:Amphibian Proteins; D002352:Carrier Proteins; D008387:Marine Toxins; D015222:Sodium Channels; C027525:saxitoxin-binding protein, Rana catesbeiana