Quantification of Multi-class Cyanopeptides in Swiss Lakes with Automated Extraction, Enrichment and Analysis by Online-SPE HPLC-HRMS/MS

The frequency and intensity of cyanobacterial blooms continue to increase in freshwater systems across the globe. Cyanobacteria can release toxins several bioactive secondary metabolites analytical methods are needed effectively assess their concentrations surface waters. Since booms evolve rapidly parts a lake, high resolution spatial temporal sampling increases complexity monitoring efforts. Here, we present validation an automated, online-solid phase extraction (SPE) performance liquid chromatography (HPLC)-high tandem mass spectrometry (HRMS/MS) method. This online-SPE HPLC-HRMS/MS enables quantitative waters for 17 peptides (cyanopeptides), spanning 5 distinct cyanopeptide classes, including: microcystins, anabaenopeptins, nodularins, cyclamides cyanopeptolins. method quantify these cyanopeptides low ng/L-range with accuracy (85-116%) relative matrix effects (<25%). We demonstrated its application Swiss lake (Zürichsee, Hallwilersee, Greifensee), which also highlighted value adding beyond common microcystins when cyanobacteria.