title: Liquid chromatography/quadrupole time-of-flight mass spectrometry for determination of saxitoxin and decarbamoylsaxitoxin in shellfish.
abstract: Saxitoxin (STX) and decarbamoylsaxitoxin (dcSTX) were determined by liquid chromatography with quadrupole time-of-flight mass spectrometry (Q-TOF MS). A shellfish tissue was extracted with 0.1 mol/l HCl under ultrasonication, and cleanup of extract was accomplished by solid-phase extraction with a C18 cartridge. Chromatographic separation was carried out on a C18 column (150 mm x 2.1 mm, 3.5 microm) with gradient elution of MeOH-H2O (20:80) containing 0.05% heptafluorobutyric acid and MeOH-H2O (15:85) containing 0.05% acetic acid. The protonated molecule [M + H]+ ions at m/z 257 for dcSTX and 300 for STX were selected in precursor ion scanning for Q-TOF MS in the positive electrospray ionizaion mode. Average recoveries and relative standard deviations, by analyzing samples spiked at a level of 0.1, 0.8 or 1.6 microg/g, were 84-92 and 8-14%, respectively. Identification of the presence of the toxins in shellfish tissues was based on the structural information offered by Q-TOF MS.
authors.affiliation: Center for Animal, Plant & Food Inspection and Quarantine, Shanghai Exit-Entry Inspection & Quarantine Bureau, 1208 Minsheng Road, Shanghai 200135, China. fangxm@shciq.gov.cn
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Fang
authors.forename: Xiang
authors.initials: X
authors.lastname: Fan
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Tang
authors.forename: Jiahua
authors.initials: J
authors.lastname: Chen
authors.forename: Jingci
authors.initials: J
authors.lastname: Lu
mesh_terms: D000818:Animals; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results; D012530:Saxitoxin / Q000031:analogs & derivatives* / Q000032:analysis*; D012758:Shellfish / Q000032:analysis*
chemical_list: D012530:Saxitoxin; C034903:decarbamylsaxitoxin