Small Molecule Ambient Mass Spectrometry Imaging by Infrared Laser Ablation Metastable-Induced Chemical Ionization
Small Molecule Ambient Mass Spectrometry Imaging by Infrared Laser Ablation Metastable-Induced Chemical Ionization
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DOI：
10.1021/ac902905v
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发表时间：
2010-03-15
影响因子：
7.4
通讯作者：
Fernandez, Facundo M.
中科院分区：
文献类型：
--
作者：
Galhena, Asiri S.;Harris, Glenn A.;Fernandez, Facundo M.
介绍了一种新型的红外激光烧蚀亚稳诱导化学电离（IR-LAMICI）环境离子源。IR-LAMICI集成了红外激光烧蚀和真实的时间（DART）直接分析--用于露天质谱（MS）电离的亚稳态诱导化学电离。IR-LAMICI源中的离子产生是两步过程。首先，IR激光脉冲撞击样品表面烧蚀表面材料。第二，烧蚀材料的一部分与亚稳态反应性羽流反应，促进分析物分子的气相化学电离，分别以正离子模式和负离子模式产生质子化或去质子化物质。红外激光烧蚀与亚稳态诱导化学电离的成功耦合产生了用于质谱（MS）的基于环境等离子体的空间分辨小分子成像平台。IR-LAMICI的分析能力通过成像药片，筛选假药和探测藻类组织表面的天然产物来探索。化学图像的分辨率由每个激光脉冲产生的凹坑大小决定，而不是由亚稳态气体射流的大小决定。使用IR-LAMICI源计算的活性药物成分（对乙酰氨基酚）的检测限为低皮克。此外，三维计算流体动力学模拟表明，在IR-LAMICI离子源的改进是可能的。
Presented here is a novel ambient ion source termed infrared laser ablation metastable-induced chemical ionization (IR-LAMICI). IR-LAMICI integrates IR laser ablation and direct analysis in real time (DART)-type metastable-induced chemical ionization for open air mass spectrometry (MS) ionization. The ion generation in the IR-LAMICI source is a two step process. First, IR laser pulses impinge the sample surface ablating surface material. Second, a portion of ablated material reacts with the metastable reactive plume facilitating gas-phase chemical ionization of analyte molecules generating protonated or deprotonated species in positive and negative ion modes, respectively. The successful coupling of IR-laser ablation with metastable-induced chemical ionization resulted in an ambient plasma-based spatially resolved small molecule imaging platform for mass spectrometry (MS). The analytical capabilities of IR-LAMICI are explored by imaging pharmaceutical tablets, screening counterfeit drugs, and probing algal tissue surfaces for natural products. The resolution of a chemical image is determined by the crater size produced with each laser pulse but not by the size of the metastable gas jet. The detection limits for an active pharmaceutical ingredient (acetaminophen) using the IR-LAMICI source is calculated to be low picograms. Furthermore, three-dimensional computational fluid dynamic simulations showed improvements in the IR-LAMICI ion source are possible.