liquid chromatography - triple quadrupole mass spectrometer (LC-MS/MS)

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For the highly sensitive and selective trace analysis and quantification of small polar molecules (mycotoxins, physiological metabolites, food ingredients, contaminants, pharmaceutical agents, signal molecules, etc.) in complex biological matrices (food samples, physiological samples, cell culture samples, tissue samples, medicinal plants, insects, etc.) the coupling of (ultra) high-performance liquid chromatography with tandem mass spectrometry ((U) HPLC-MS / MS) is the method of choice. Many molecular relationships in the food-chemical-toxicological context but also in pharmaceutical-biological issues can only be answered in complex test systems in vitro or in vivo. In the case of potent contaminants or active substances in particular, this means that extremely low concentrations often have to be analyzed in order to obtain meaningful data. If, for example, the analyte content in individual cell compartments has to be quantified or metabolites have to be characterized by their production spectrum, the demands on the performance of the analytical system increase further. In the area of human biomonitoring, the requirements with regard to detection and quantification limit are also extremely high, since here the lowest concentrations of contaminants such as mycotoxins and their metabolites must be determined in physiological samples in order to enable a meaningful determination of human exposure. In cohort studies using the biomonitoring of mycotoxins, this means that the amount of left censored data, i.e. analytical results with levels below the detection limit, essentially determines the significance of the observed relationships and influencing variables. At the same time, the cohort size is also essential for the informative value of intervention studies. The SHINE study with several thousand urine samples should be mentioned here as an example, with these orders of magnitude complex sample preparations are not possible. For this reason, a highly sensitive triple quadrupole mass spectrometer in connection with a UHPLC system and online solid phase extraction is applied for. An additional further fragmentation possibility via an ion trap (QTRAP) is also intended to achieve increased selectivity, and it is also possible to generate production spectra in the lowest concentration range for better characterization of unknown metabolites.