Scientific Publications by FDA Staff

J Agric Food Chem 2015 Dec 2;63(47):10303-12

Development and validation of a liquid chromatography-tandem mass spectrometry method for the quantitation of microcystins in blue-green algal dietary supplements.

Parker CH, Stutts WL, DeGrasse SL

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 mug/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 mug/g) and quantitation (0.018-0.084 mug/g) were sufficient to confirm the presence of microcystin contamination at the Oregon-mandated guidance concentration of 1.0 mug 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 mug 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.