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

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 carr...