title: Improving derivatization efficiency of BMAA utilizing AccQ-Tag in a complex cyanobacterial matrix.
abstract: Two different assays have been developed and used in order to investigate the optimal conditions for derivatization and detection of acid beta-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.
authors.affiliation: Department of Botany, Stockholm University, 10691, Stockholm, Sweden. johan.eriksson@botan.su.se
authors.forename: Johan
authors.initials: J
authors.lastname: Eriksson
authors.forename: Sara
authors.initials: S
authors.lastname: Jonasson
authors.forename: Dimitra
authors.initials: D
authors.lastname: Papaefthimiou
authors.forename: Ulla
authors.initials: U
authors.lastname: Rasmussen
authors.forename: Birgitta
authors.initials: B
authors.lastname: Bergman
mesh_terms: D000599:Amino Acids, Diamino / Q000737:chemistry*; D000458:Cyanobacteria / Q000737:chemistry*; D000087522:Cyanobacteria Toxins; D007201:Indicator Dilution Techniques
chemical_list: D000599:Amino Acids, Diamino; D000087522:Cyanobacteria Toxins; C001824:beta-N-methylamino-L-alanine