Laser Ablation Coupled to a Flowing Atmospheric Pressure Afterglow for Ambient Mass Spectral Imaging
Laser Ablation Coupled to a Flowing Atmospheric Pressure Afterglow for Ambient Mass Spectral Imaging
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DOI：
10.1021/ac801594u
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发表时间：
2008-11-01
影响因子：
7.4
通讯作者：
Hieftje, Gary M.
中科院分区：
文献类型：
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作者：
Shelley, Jacob T.;Ray, Steven J.;Hieftje, Gary M.
使用基于等离子体的环境解吸/电离质谱（ADI-MS）源进行分子质谱成像。通过将266 nm激光聚焦到光斑上烧蚀少量样品材料。通过氮气流将所得气溶胶转移到氦大气压辉光放电电离源的流动余辉中;通过Leco Unique飞行时间质谱仪分析电离的样品材料。二维质谱图像是通过在样品表面上扫描激光束产生的。6 mm（2）表面的总分析时间（受消融室冲洗的限制）小于30 min。采用该技术，已实现类似于20 pin的空间分辨率。此外，激光烧蚀配置用于获得超过2分钟的深度信息，分辨率类似于40 μ m。激光烧蚀与流动的大气压余辉源的组合用于分析多种分析物的几个样品表面，并具有高灵敏度（咖啡因的LOD为5 fmol）。
A plasma-based ambient desorption/ionization mass spectrometry (ADI-MS) source was used to perform molecular mass spectral imaging. A small amount of sample material was ablated by focusing 266 nm laser light onto a spot. The resulting aerosol was transferred by a nitrogen stream to the flowing afterglow of a helium atmospheric pressure glow discharge ionization source; the ionized sample material was analyzed by a Leco Unique time-of-flight mass spectrometer. Two-dimensional mass spectral images were generated by scanning the laser beam across a sample surface. The total analysis time for a 6 mm(2) surface, which is limited by the washout of the ablation chamber, was less than 30 min. With this technique, a spatial resolution of similar to 20 pin has been achieved. Additionally, the laser ablation configuration was used to obtain depth information of over 2 min with a resolution of similar to 40 pm. The combination of laser ablation with the flowing atmospheric pressure afterglow source was used to analyze several sample surfaces for a wide variety of analytes and with high sensitivity (LOD of 5 fmol for caffeine).