Research Centre for Biochemistry and Food Technology, National Research Institute of Fisheries Science, 2-12-4 Fukuura, Yokohama 236-8648, Japan.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2013;30(8):1351-7. doi: 10.1080/19440049.2013.793456. Epub 2013 Jun 2.
We developed a sample preparation and LC-MS/MS method for the determination of saxitoxins in toxic algae. Paralytic shellfish toxins (PSTs) were successfully separated by gradient elution on an amide column with the hydrophilic interaction mode and quantified with multiple reaction monitoring (MRM) detection in the positive ion mode. This method showed good performance in the summed LODs and LOQs for all 12 toxins, 25 and 84 nM, respectively. Next, extracts of cultured strains of a toxic dinoflagellate Alexandrium tamarense and a freshwater cyanobacteria Anabaena circinalis were treated in a short column of basic alumina and the toxic fractions were analysed by our LC-MS/MS method and by HPLC with fluorescence detection. Comparison of the results obtained by the two methods demonstrated that approximately equivalent results were obtained for both the dinoflagellate and the cyanobacteria. In addition, the retention time of the toxins showed acceptable shifts. Therefore, the clean-up of the toxic algal extracts by using the basic alumina column controlled unwanted chromatographic behaviour and variable ionisation efficiency during MS detection. LC-MS/MS for saxitoxins has great potential as a rapid analytical method for determining all primary saxitoxins in cultured algae.
我们开发了一种用于检测毒性藻类中石房蛤毒素的样品制备和 LC-MS/MS 方法。采用酰胺柱和亲水作用模式的梯度洗脱，成功分离了麻痹性贝类毒素（PSTs），并采用正离子模式下的多重反应监测（MRM）检测进行定量。该方法对所有 12 种毒素的总和检出限和定量限均表现出良好的性能，分别为 25 和 84 nM。接下来，用碱性氧化铝短柱处理培养的有毒甲藻亚历山大藻和淡水蓝藻鱼腥藻的提取物，并通过我们的 LC-MS/MS 方法和 HPLC 荧光检测分析有毒馏分。两种方法的结果比较表明，两种甲藻和蓝藻的结果基本相当。此外，毒素的保留时间也有可接受的偏移。因此，使用碱性氧化铝柱对有毒藻类提取物进行净化可以控制在 MS 检测过程中不想要的色谱行为和可变的离子化效率。LC-MS/MS 法用于石房蛤毒素具有很大的潜力，可作为一种快速分析方法，用于测定培养藻类中的所有初级石房蛤毒素。
