Li Ming, Hu Bin, Li Jianqiang, Chen Rong, Zhang Xie, Chen Huanwen
Department of Applied Chemistry, East China Institute of Technology, Fuzhou 344000, PR China.
Anal Chem. 2009 Sep 15;81(18):7724-31. doi: 10.1021/ac901199w.
A homemade novel nanoextractive electrospray ionization (nanoEESI) source has been characterized for in situ mass spectrometric analysis of ambient samples without sample pretreatment. The primary ions generated using a nanospray emitter interact with the neutral sample plume created by manually nebulizing liquid samples, allowing production of the analyte ions in the spatial cross section of the nanoEESI source. The performance of nanoEESI is experimentally investigated by coupling the nanoEESI source to a commercial LTQ mass spectrometer for rapid analysis of various ambient samples using positive/negative ion detection modes. Compounds of interest in actual samples such as aerosol drug preparations, beverages, milk suspensions, farmland water, and groundwater were unambiguously detected using tandem nanoEESI ion trap mass spectrometry. The limit of detection was low picogram per milliliter levels for the compounds tested. Acceptable relative standard deviation (RSD) values (5-10%) were obtained for direct measurement of analytes in complex matrixes, providing linear dynamic signal responses using manual sample introduction. A single sample analysis was completed within 1.2 s. Requiring no sheath gas for either primary ion production or neutral sample introduction, the nanoEESI has advantages including readiness for miniaturization and integration, simple maintenance, easy operation, and low cost. The experimental data demonstrate that the nanoEESI is a promising tool for high-throughput, sensitive, quantitative, in situ analysis of ambient complex samples, showing potential applications for in situ analysis in multiple disciplines including but not limited to pharmaceutical analysis, food quality control, pesticides residue detection, and homeland security.
一种自制的新型纳米萃取电喷雾电离（nanoEESI）源已被表征，可用于对环境样品进行原位质谱分析，无需样品预处理。使用纳米喷雾发射器产生的初级离子与通过手动雾化液体样品产生的中性样品羽流相互作用，从而在nanoEESI源的空间横截面中产生分析物离子。通过将nanoEESI源与商用LTQ质谱仪耦合，利用正/负离子检测模式对各种环境样品进行快速分析，对nanoEESI的性能进行了实验研究。使用串联nanoEESI离子阱质谱法明确检测了实际样品中感兴趣的化合物，如气溶胶药物制剂、饮料、牛奶悬浮液、农田水和地下水。所测试化合物的检测限为每毫升低皮克水平。对于复杂基质中分析物的直接测量，获得了可接受的相对标准偏差（RSD）值（5-10%），使用手动进样提供了线性动态信号响应。单个样品分析在1.2秒内完成。nanoEESI在初级离子产生或中性样品引入方面都不需要鞘气，具有易于小型化和集成、维护简单、操作方便和成本低等优点。实验数据表明，nanoEESI是一种用于高通量、灵敏、定量、原位分析环境复杂样品的有前途的工具，在包括但不限于药物分析、食品质量控制、农药残留检测和国土安全等多个学科的原位分析中显示出潜在应用。
