Tebuconazole belongs to widely utilized plant fungicides, mostly in vineyards. Its traces are present in plant tissues, wine as well as in soil. The aim of the study was to determine stoichiometries and stabilities of metal (Cu, Zn, Cd, Ca and Ag) complexes with tebuconazole (1) by means of electrospray ionization mass spectrommetry (ESI-MS). It was found that the complexes of tebuconazole with copper ions are particularly stable ([Cu(1)]+ has appearance energy 224 kJ·mol-1 , corresponding with the dissociation of the water molecule from the tebuconazole molecule), while the stability of another tebuconazole complexes is lower, about 150 kJ·mol-1 . In real environmental samples, the detection of 1 itself is hampered by its spreading into various species. The method involved here is based upon a hyphenation of electrochemistry (amperometry) and electrospray-ionization mass spectrometry (ESI-MS). It uses the fact that Cu creates very stable complexes with 1. We demonstrate that at appropriate potentials (at higher than 500 mV) Cu cations can be generated in an electrochemical cell and subsequently form complexes with 1 present in the sample. The resulting complex [Cu(1)]+ is detected with ESI-MS. The intensity of detected complexes depends on the concentration of 1 and the oxidation level of the...
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:307076 |
| Date | January 2012 |
| Creators | Norková, Renáta |
| Contributors | Jaklová Dytrtová, Jana, Vyskočil, Vlastimil |
| Source Sets | Czech ETDs |
| Language | Czech |
| Detected Language | English |
| Type | info:eu-repo/semantics/masterThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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