A Collaborative Evaluation of LC-MS/MS Based Methods for BMAA Analysis: Soluble Bound BMAA Found to Be an Important Fraction

• Main Authors: Elisabeth J. Faassen, Maria G. Antoniou, Wendy Beekman-Lukassen, Lucie Blahova, Ekaterina Chernova, Christophoros Christophoridis, Audrey Combes, Christine Edwards, Jutta Fastner, Joop Harmsen, Anastasia Hiskia, Leopold L. Ilag, Triantafyllos Kaloudis, Srdjan Lopicic, Miquel Lürling, Hanna Mazur-Marzec, Jussi Meriluoto, Cristina Porojan, Yehudit Viner-Mozzini, Nadezda Zguna
• Format: Article
• Language: English
• Published: MDPI AG 2016-02-01
• Series: Marine Drugs
• Subjects: β-N-methylamino-; ">l-alanine (BMAA); 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC); α,γ-diaminobutyric acid (DAB); cycad; Daphnia magna; hydrophilic interaction liquid chromatography (HILIC); Internal standard; Liquid chromatography-tandem mass spectrometry (LC-MS/MS); N-(2-aminoethyl) glycine (AEG); phytoplankton; seafood
• Online Access: http://www.mdpi.com/1660-3397/14/3/45

Exposure to β-N-methylamino-l-alanine (BMAA) might be linked to the incidence of amyotrophic lateral sclerosis, Alzheimer’s disease and Parkinson’s disease. Analytical chemistry plays a crucial role in determining human BMAA exposure and the associated health risk, but the performance of various analytical methods currently employed is rarely compared. A CYANOCOST initiated workshop was organized aimed at training scientists in BMAA analysis, creating mutual understanding and paving the way towards interlaboratory comparison exercises. During this workshop, we tested different methods (extraction followed by derivatization and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis, or directly followed by LC-MS/MS analysis) for trueness and intermediate precision. We adapted three workup methods for the underivatized analysis of animal, brain and cyanobacterial samples. Based on recovery of the internal standard D3BMAA, the underivatized methods were accurate (mean recovery 80%) and precise (mean relative standard deviation 10%), except for the cyanobacterium Leptolyngbya. However, total BMAA concentrations in the positive controls (cycad seeds) showed higher variation (relative standard deviation 21%–32%), implying that D3BMAA was not a good indicator for the release of BMAA from bound forms. Significant losses occurred during workup for the derivatized method, resulting in low recovery (<10%). Most BMAA was found in a trichloroacetic acid soluble, bound form and we recommend including this fraction during analysis.