title: Methods for detection of anatoxin-a(s) by liquid chromatography coupled to electrospray ionization-tandem mass spectrometry.
abstract: Anatoxin-a(s) is a potent irreversible inhibitor of the enzyme acetylcholinesterase with a unique N-hydroxyguanidine methylphosphate ester chemical structure. Determination of this toxin in environmental samples is hampered by the lack of specific methods for its detection. Using the toxic strain of Anabaena lemmermani PH-160 B as positive control, the fragmentation characteristics of anatoxin-a(s) under collision-induced dissociation conditions have been investigated and new LC-MS/MS methods proposed. Recommended ion transitions for correct detection of this toxin are 253>58, 253>159, 235>98 and 235>96. Chromatographic separation is better achieved under HILIC conditions employing a ZIC-HILIC column. This method was used to confirm for the first time the production of anatoxin-a(s) by strains of Anabaena oumiana ITEP-025 and ITEP-026. Considering no standard solutions are commercially available, our results will be of significant use for the correct identification of this toxin by LC-MS/MS.
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Avenida Lineu Prestes, 580, 05508900 São Paulo, SP, Brazil.
authors.forename: Felipe Augusto
authors.initials: FA
authors.lastname: Dörr
authors.forename: Vania
authors.initials: V
authors.lastname: Rodríguez
authors.forename: Renato
authors.initials: R
authors.lastname: Molica
authors.forename: Peter
authors.initials: P
authors.lastname: Henriksen
authors.forename: Bernd
authors.initials: B
authors.lastname: Krock
authors.forename: Ernani
authors.initials: E
authors.lastname: Pinto
mesh_terms: D000110:Acetylcholinesterase / Q000097:blood; D017033:Anabaena / Q000737:chemistry; D002800:Cholinesterase Inhibitors / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D056148:Chromatography, Reverse-Phase; D000087522:Cyanobacteria Toxins; D006801:Humans; D008387:Marine Toxins / Q000032:analysis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry; D014326:Tropanes / Q000032:analysis* / Q000737:chemistry
chemical_list: D002800:Cholinesterase Inhibitors; D000087522:Cyanobacteria Toxins; D008387:Marine Toxins; D014326:Tropanes; C509785:anatoxin-a(s); D000110:Acetylcholinesterase