Pyrolytic behaviour of microcystins and microcystin-spiked algal blooms

This work describes the pyrolytic behaviour of microcystin (MC) standards using both conventional analytical pyrolysis (Py-GC-MS) and thermochemolysis with tetramethylammonium hydroxide (TMAH). In both cases, the pyrolytic patterns of the MCs at low pyrolysis temperature were structure-dependant, which confirms that pyrolytic techniques are suitable to readily distinguish between different types of MCs. However, the different types of amino acids conforming the structure of the MCs were distinguished only after TMAH/thermochemolysis. In order to examine the suitability of such techniques as a potential tool in the analysis of MC in cyanobacterial algae blooms, pyrolytic experiments using cyanobacterial cultures spiked with the microcystin LR (MC-LR) were also performed. The results suggest that pyrolytic techniques could be used for the rapid and safe detection of toxins in cyanobacterial blooms. Although promissory, further work directed to technique optimization would be necessary before this methodology is used as a routine detection method.