Use of electrospray ionization (ESI) mass spectrometry to investigate complex dissolved organic matter (DOM) and its potential applications in phytoplankton research

Organic nutrients are one of many factors considered to be important in the growth and proliferation of phytoplankton including many species that cause harmful algal blooms (HABs). Several studies have investigated the effects of known organic compounds on phytoplankton growth, however, the role of natural dissolved organic matter (DOM) in phytoplankton nutrition remains understudied at the compound level. This lack of research is due in part to analytical limitations for the characterization of DOM compounds. Electrospray ionization (ESI) mass spectrometry (MS) provides an unprecedented level of chemical information on thousands of organic compounds that comprise the bulk DOM pool. In this paper we provide a brief overview of some of the benefits and caveats of using ESI to investigate DOM in natural freshwater and marine systems and show an example of ESI-MS DOM characterization for a natural bloom of the raphidophyte Chattonella cf. verruculosa.