Environmental and Bio-Analytical Laboratories, Department of Chemistry, Sharif University of Technology, Tehran, Iran.
J Sep Sci. 2012 Jan;35(1):114-20. doi: 10.1002/jssc.201100509. Epub 2011 Dec 5.
A novel method based on microextraction in packed syringe (MEPS) as sample preparation technique coupled off-line with gas chromatography-mass spectrometry was developed using electrospun nanofibers as sorbent. For electrospinning of polypyrrole/polyamide-based nanofiber, a homogeneous solution containing nylon 6, ferric chloride and pyrrole monomer was prepared and then was drawn into a 2.5-mL syringe. By applying a voltage of 13 kV between the needle of the syringe and an aluminum-foil collector, the nanofibers could be formed on the surface of the collector. The prepared sheet was used as the sorbent for MEPS to analyze some selected organophosphorous pesticides. Important parameters influencing the extraction and desorption processes were optimized. Limits of detection were in the range of 0.04-0.1 ng/mL using time scheduled selected ion monitoring mode, and the relative standard deviation (RSD %) values with four replicates were in the range of 3.7-11.8% at a concentration level of 5 ng/mL. The linearity of the method was in the range of 0.5-500 ng/mL for diazinon and fenithrothion and 0.5-200 ng/mL for the rest of the analytes. The developed method was successfully applied to Zayandeh-roud river water samples, whereas the matrix factors were in the range of 0.87-0.98.
基于微萃取填充注射器（MEPS）的新型方法作为样品制备技术，与离线气相色谱-质谱联用，使用电纺纳米纤维作为吸附剂。为了制备聚吡咯/聚酰胺基纳米纤维，制备了包含尼龙 6、三氯化铁和吡咯单体的均相溶液，然后将其吸入 2.5mL 注射器中。通过在注射器的针和铝箔收集器之间施加 13 kV 的电压，可以在收集器表面形成纳米纤维。制备的薄片用作 MEPS 的吸附剂，以分析一些选定的有机磷农药。优化了影响萃取和解吸过程的重要参数。使用时间程序选择离子监测模式，检测限范围为 0.04-0.1ng/mL，在 5ng/mL 浓度水平下，四个重复的相对标准偏差（RSD%）值在 3.7-11.8%范围内。该方法的线性范围为 0.5-500ng/mL 的敌百虫和fenithrothion，以及 0.5-200ng/mL 的其余分析物。开发的方法成功应用于扎扬德河河水样品，而基质因子在 0.87-0.98 范围内。
