Rapid Microcystin Determination Using a Paper Spray Ionization Method with a Time-of-Flight Mass Spectrometry System.

The eutrophication of surface water sources and climate changes have resulted in an annual explosion of cyanobacterial blooms in many irrigating and drinking water resources. To decrease health risks to the public, a rapid real time method for the synchronous determination of two usually harmful microcystins (MC-RR and MC-LR) in environmental water samples was built by employing a paper spray ionization method coupled with a time-of-flight mass spectrometer system. With this approach, direct analysis of microcystin mixtures without sample preparation has been achieved. Rapid detection was performed, simulating the release process of microcystins in reservoir water samples, and the routine detection frequency was every three minutes. The identification time of microcystins was reduced from several hours to a few minutes. The limit of detection is 1 mu g/L, and the limit of quantitation is 3 mu g/L. This method displays the ability for carrying out rapid, direct, and high-throughput experiments for determination of microcystins, and it would be of significant interest for environmental and food safety applications.