Forschungsanstalt Geisenheim, Fachgebiet Mikrobiologie und Biochemie, Von-Lade-Strasse 1, D-65366 Geisenheim, Germany.
Anal Chim Acta. 2010 Feb 15;660(1-2):76-80. doi: 10.1016/j.aca.2009.11.050. Epub 2009 Dec 3.
The aim of this research work was focused on the replacement of the time-consuming soaking of cork stoppers which is mainly used as screening method for cork lots in connection with sensory analysis and/or analytical methods to detect releasable 2,4,6-trichloroanisole (TCA) of natural cork stoppers. Releasable TCA from whole cork stoppers was analysed with the application of a microwave assisted extraction method (MAE) in combination with stir bar sorptive extraction (SBSE). The soaking of corks (SOAK) was used as a reference method to optimise MAE parameters. Cork lots of different quality and TCA contamination levels were used to adapt MAE. Pre-tests indicated that an MAE at 40 degrees C for 120 min with 90 min of cooling time are suitable conditions to avoid an over-extraction of TCA of low and medium tainted cork stoppers in comparison to SOAK. These MAE parameters allow the measuring of almost the same amounts of releasable TCA as with the application of the soaking procedure in the relevant range (<25 ng L(-1) releasable TCA from one cork) to evaluate the TCA level of cork stoppers. Stable isotope dilution assay (SIDA) was applied to optimise quantification of the released TCA with deuterium-labelled TCA (TCA-d(5)) using a time-saving GC-MS technique in single ion monitoring (SIM) mode. The developed MAE method allows the measuring of releasable TCA from the whole cork stopper under improved conditions and in connection with a low use of solvent and a higher sample throughput.
本研究工作的目的集中在取代耗时的软木塞浸泡，该浸泡主要用于感官分析和/或分析方法来检测天然软木塞中可释放的 2,4,6-三氯苯甲醚（TCA），作为软木塞批次的筛选方法。采用微波辅助提取法（MAE）结合搅拌棒吸附萃取（SBSE），对整个软木塞中的可释放 TCA 进行分析。软木塞浸泡（SOAK）用作优化 MAE 参数的参考方法。使用不同质量和 TCA 污染水平的软木塞批次来适应 MAE。预试验表明，在 40°C 下提取 120 分钟，并冷却 90 分钟，是避免低污染和中污染软木塞过度提取 TCA 的合适条件，与 SOAK 相比。这些 MAE 参数允许测量与浸泡程序相同的可释放 TCA 量，以评估软木塞的 TCA 水平。采用稳定同位素稀释测定法（SIDA），应用氘标记 TCA（TCA-d(5)），通过耗时的 GC-MS 技术，在单离子监测（SIM）模式下优化释放 TCA 的定量分析。所开发的 MAE 方法允许在改进的条件下测量整个软木塞中的可释放 TCA，并结合使用较少的溶剂和更高的样品通量。
