LCMS-SOP Determination of Microcystins in Water Samples by High Performance Liquid Chromatography (HPLC) with Single Quadrupole Mass Spectrometry (MS) v1
Gregory L. Boyer
Abstract
This standard operating procedure is used to determine and quantify microcystins and nodularin (intracellular and/or extracellular) in whole water samples or filter samples using HPLC-coupled with single quadrupole mass spectrometry (LC-MS). The method described here is a modification of the methods described in Boyer (2007) for particulate microcystins in water samples and does not use solid phase extraction. It was designed to use a 50% acidified methanolic extraction solvent, but is compatible with protocols for direct water analysis (US-EPA, 2016) and higher concentration methanolic extracts (Cerasino et al., 2017). It is not suitable for use with tissues samples or other samples with complex matrix interferences, such as soil or sediments. The method is designed for high throughput (1000-1500 injections per month) using a low-resolution (unit mass) mass spectrometer. It gives results of similar accuracy to the commonly used Abraxis ADDA ELISA with additional information on the microcystin congener profiles.