Search

β-N-methylamino-l-alanine (BMAA) is a non-protein amino acid, thought to be inflicting neurodegenerative diseases related to ALS/PDC in human beings. Due to conflicting data concerning the presence of BMAA in various biological matrixes, we present a robust and sensitive method for high confidence identification of BMAA after derivatization by 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). The efficient sample pretreatment in combination with LC-MS/MS SRM enables chromatographic separation of BMAA from the isomer 2,3-diaminobutyric acid (DAB). The method is applicable for selective BMAA/DAB detection in various biological samples ranging from a prokaryotic cyanobacterium to eukaryotic fish. [ABSTRACT FROM AUTHOR]

Abstract  Two different assays have been developed and used in order to investigate the optimal conditions for derivatization and detection of acid β-N-methyl-amino-l-alanine (BMAA) in a cyanobacterial sample. BMAA was extracted from cyanobacterial cultures both from the cytosolic (“free”) fraction and in the precipitated (“protein”) fraction using a newly developed extraction scheme and the sample matrix was standardized according to protein concentration to ensure the highest possible derivative yield. A rapid and sensitive HPLC method for fluorescence detection of the non-protein amino acid BMAA in cyanobacteria, utilizing the Waters AccQ-Tag® chemistry and Chromolith® Performance RP-18e columns was developed. Using this new method and utilizing a different buffer system and column than that recommended by Waters, we decreased the time between injections by 75%. The limit of quantification was determined to be 12 nmol and limit of detection as 120 fmol. The linear range was in the range of 8.5 nmol–84 pmol. Accuracy and precision were well within FDA guidelines for bioanalysis. [ABSTRACT FROM AUTHOR]