title: Detection and confirmation of saxitoxin analogues in freshwater benthic Lyngbya wollei algae collected in the St. Lawrence River (Canada) by liquid chromatography-tandem mass spectrometry.
abstract: The presence of cyanotoxins in benthic Lyngbya wollei algae samples collected in a fluvial lake along the St. Lawrence River, Canada, was investigated using a multi-toxins method. Hydrophilic interaction liquid chromatography (HILIC) and reverse phased liquid chromatography (RPLC) were coupled to triple quadrupole mass spectrometry (LC-QqQMS) for quantification and to quadrupole-time of flight mass spectrometry (LC-QqTOFMS) for screening and confirmation. The presence of two saxitoxin analogues, LWTX-1 and LWTX-6, was confirmed in benthic Lyngbya wollei algae samples. Concentration of LWTX-1 was between 209±5 and 279±9 μg g(-1). No other targeted cyanotoxin (such as anatoxin-a, nodularin, microcystin-LR, microcystins-RR and saxitoxin) was found in the samples. The presence of LWTX-6 was observed by using a screening approach based on an in-house database of cyanotoxins, an algorithm of identification and high resolution mass spectrometry measurements on the precursor and product ions. This work demonstrates the need for more research on the fate of benthic cyanotoxins in aquatic ecosystems such the St. Lawrence River.
authors.affiliation: Aquatic Ecosystems Protection Research Division, Environment Canada, Montreal, QC, Canada.
authors.forename: André
authors.initials: A
authors.lastname: Lajeunesse
authors.forename: Pedro A
authors.initials: PA
authors.lastname: Segura
authors.forename: Malorie
authors.initials: M
authors.lastname: Gélinas
authors.forename: Christiane
authors.initials: C
authors.lastname: Hudon
authors.forename: Krista
authors.initials: K
authors.lastname: Thomas
authors.forename: Michael A
authors.initials: MA
authors.lastname: Quilliam
authors.forename: Christian
authors.initials: C
authors.lastname: Gagnon
mesh_terms: D001427:Bacterial Toxins / Q000032:analysis* / Q000737:chemistry; D002170:Canada; D002853:Chromatography, Liquid / Q000379:methods*; D000458:Cyanobacteria / Q000737:chemistry*; D046869:Dolichospermum flos-aquae; D057097:Harmful Algal Bloom; D057927:Hydrophobic and Hydrophilic Interactions; D045483:Rivers / Q000382:microbiology; D012530:Saxitoxin / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D001427:Bacterial Toxins; D012530:Saxitoxin