LC/Q-TOF mass spectrometer

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Modern characterization of inorganic compounds and metal complexes requires the recording of accurate high-resolution mass spectra. These spectra are not only used to prove the identity of compounds, but also for the elucidation of reaction mechanisms and pathways. They furthermore enable a precise synthesis planning and allow metabolic studies of potential inorganic therapeutics. In accordance with the utilization concept for mass spectrometry of the faculty of Chemistry and Pharmacy, routine mass spectra are recorded in one of the service units of the faculty. The service unit in the Institute of Inorganic and Analytical Chemistry is specialized in the characterization of inorganic compounds such as metal complexes, and their ligands. The broad spectrum of sample types imposes high standards on the requested instrument: potential analytes range from small low-molecular compounds to coordination complexes with biomolecule-based ligands. Therefore, a combination of tandem mass spectrometry with the possibility of an upstream chromatographic separation with simultaneous recording of absorbance spectra by a diode-array detector (DAD) is required. Particularly in the context of bioinorganic samples, a chromatographic separation of complex sample mixtures facilitates metabolism studies or allows to reduce the salt load. The UV/vis activity of many biomolecules further enables a correlation of the signals in the absorbance spectra (recorded by the DAD) and the respective mass spectra, allowing to draw conclusions regarding the association of complex and biomolecule. For the detection of intact adducts, a mild non-fragmenting ionization is required, as interactions with complexes and metal ions can be weak. Hence, the requested instrument should be equipped with electrospray ionization and should be capable of optionally applying a cryospray source, allowing the characterization of highly thermo-labile adducts. To enable a wide scope of applications, the instrument should provide APCI as an alternative ionization source, allowing to deal with low-polarity analytes (APCI, atmospheric pressure chemical ionization).