title: Development and Validation of a Liquid Chromatography-Tandem Mass Spectrometry Method for the Quantitation of Microcystins in Blue-Green Algal Dietary Supplements.
abstract: A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous detection and quantitation of seven microcystin congeners (1-7) and nodularin-R (8) in blue-green algal dietary supplements. Single-laboratory method validation data were collected in four supplement matrices (capsule, liquid, powder, and tablet) fortified at toxin concentrations from 0.25-2.00 μg/g (ppm). Average recoveries and relative standard deviations (RSD) using matrix-corrected solvent calibration curves were 101% (6% RSD) for all congeners and supplements investigated. Limits of detection (0.006-0.028 μg/g) and quantitation (0.018-0.084 μg/g) were sufficient to confirm the presence of microcystin contamination at the Oregon-mandated guidance concentration of 1.0 μg of microcystin-LReq/g. Quantitated concentrations of microcystin contamination in market-available Aphanizomenon flos-aquae blue-green algal supplements ranged from 0.18-1.87 μg of microcystin-LReq/g for detected congeners microcystin-LR, microcystin-LA, and microcystin-LY (3-5). Microcystin-RR, -YR, -LW, and -LF and nodularin-R (1, 2, and 6-8) were not detected in the supplements examined.
authors.affiliation: U.S. Food and Drug Administration , Center for Food Safety and Applied Nutrition, 5100 Paint Branch Parkway, College Park, Maryland 20740, United States.
authors.forename: Christine H
authors.initials: CH
authors.lastname: Parker
authors.affiliation: U.S. Food and Drug Administration , Center for Food Safety and Applied Nutrition, 5100 Paint Branch Parkway, College Park, Maryland 20740, United States.
authors.forename: Whitney L
authors.initials: WL
authors.lastname: Stutts
authors.affiliation: U.S. Food and Drug Administration , Center for Food Safety and Applied Nutrition, 5100 Paint Branch Parkway, College Park, Maryland 20740, United States.
authors.forename: Stacey L
authors.initials: SL
authors.lastname: DeGrasse
mesh_terms: D001427:Bacterial Toxins / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D000458:Cyanobacteria / Q000737:chemistry*; D019587:Dietary Supplements / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis; D052998:Microcystins / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D001427:Bacterial Toxins; D052998:Microcystins; C078588:microcystin
keywords: Aphanizomenon flos-aquae; blue-green algae; cyanotoxin; dietary supplements; microcystin; tandem mass spectrometry