a Pesticide Residue Research Group , University of Almería , Almería , Spain.
J Environ Sci Health B. 2014;49(8):541-9. doi: 10.1080/03601234.2014.911553.
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 (RSD > 50%) and ranged between 10% and 45% (related to the signal obtained for derivatization in vial).
已评估用不同试剂和溶剂对菌核利进行衍生化，以改善其气相色谱/质谱（GC/MS）特性。在评估了一些初步的酰化和硅烷化反应后，选择无水七氟丁酸酐（HFBA）衍生化作为菌核利的最佳衍生化选择。通过 GC/MS（离子阱）清楚地鉴定和表征了 HFBA-菌核利衍生物。菌核利 HFBA 衍生物的谱图特征为基峰，252 m/z 离子，以及另外两个相对丰度为 5%（224 m/z 离子）和 4%（420 m/z 分子离子）的离子。在 25°C 温度下，无溶剂、0.1-1μg 菌核利在小瓶中衍生化 120 分钟，用 5μL HFBA 和 5μL 吡啶时，转化率在 83-92%范围内。在无改性剂存在的情况下，仅在超临界二氧化碳中同时进行菌核利提取衍生化，但在 50°C 和 200 大气压（n=5）、300 大气压（n=7）和 400 大气压（n=5）下进行的重复实验中获得的转化率/回收率不可重复（RSD＞50%），范围在 10%-45%之间（与小瓶衍生化获得的信号相关）。
