Assessing solvent derivatization and carbon dioxide supercritical fluid simultaneous extraction/derivatization of cyprodinil

Autor: Antonio Valverde, Mourad Boulaid, Ana Aguilera, Luis García-Fuentes, Antonio Valverde-Monterreal
Rok vydání: 2014
Předmět:
Zdroj: Journal of Environmental Science and Health, Part B. 49:541-549
ISSN: 1532-4109
0360-1234
Popis: Derivatization of cyprodinil with different reagents and solvents has been evaluated to improve the GC/MS characterization of this fungicide. After assessing some preliminary acylation and silylation reactions, derivatization with anhydrous heptafluorobutyric anhydride (HFBA) was selected as the best derivatization option for cyprodinil. The HFBA-cyprodinil derivative was clearly identified and characterized by GC/MS (ion-trap). The spectrum of the HFBA derivative of cyprodinil was characterized by the base peak, 252 m/z ion, and two other ions with relative abundances of 5% (224 m/z ion) and 4% (420 m/z molecular ion). Conversion rates in the range of 83-92% were obtained when 0.1-1 μg cyprodinil were derivatized in vial without solvent at 25ºC temperature for 120 min, with 5 μL HFBA and 5 μL pyridine. Simultaneous extraction-derivatization of cyprodinil in supercritical carbon dioxide was only achieved when no modifier was present, but conversion/recovery rates obtained in the replicate experiments carried out with 15 mL supercritical carbon dioxide at 50°C and 200 atm (n = 5), 300 atm (n = 7), and 400 atm (n = 5) were no reproducible (RSD50%) and ranged between 10% and 45% (related to the signal obtained for derivatization in vial).
Databáze: OpenAIRE
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