Analysis of Microcystins in Spirulina Products by High Performance Liquid Chromatography - Electrospray lonization Mass Spectrometry

摘要

Microcystins are a group of structurally similar cyclic heptapeptide hepatotoxins and tumor promoters, produced by cyanobacteria. A microbore liquid chromatography electros-pray ionization mass spectrometry(LC -ESI -MS) method has been developed which is capable of separating and detecting trace amounts of microcystin variants in different samples. More than 30 samples of Spirulina, in the form of pills, capsules, and powders were collected from retail outlets from across China. The samples were extracted with 5% acetic acid in water and centrifuged to remove solids. After sample cleanup using C18 solid - phase extraction the LC - MS method measured specific microcystins (LR, RR) using external standards of these for identification and quantification, the results obtained very well over a concentration range of about 0.5 - 20 μg/g. Microcystin RR was found in all positive samples , microcystin LR was the only other microcystin found in the samples analyzed. The study demonstrated that LC - ESI - MS is a reliable and sensitive technique for analysing trace levels of microcystins in spirulina health food products.