Department of Chemistry, University of California, Riverside, California 92521, USA.
Analyst. 2020 Apr 7;145(7):2639-2648. doi: 10.1039/c9an02534k. Epub 2020 Feb 17.
Recent experimental efforts have shown that single particle levitation methods may be effectively coupled with mass spectrometry (MS) using paper spray (PS) ionization for compositional analysis of picoliter droplets. In this work, we characterize the response of PS-MS to analytes delivered in the form of picoliter droplets and explore its potential for identification and quantification of these samples. Using a microdroplet dispenser to generate droplets, we demonstrate sensitivity to a range of oxygenated organic molecules typical of compounds found in atmospheric secondary organic aerosol. We assess experimental factors that influence the reproducibility and sensitivity of the method and explore the linearity of the system response to increasing analyte mass in droplets containing single or multicomponent analytes. We show that the ratio of analyte signal from multicomponent samples may be used to characterize the relative composition of the system. These measurements demonstrate that the droplet PS-MS method is an effective tool for qualitative and quantitative analysis of single picoliter droplets containing picogram levels of analyte. The potential applications of this technique for characterizing the composition of levitated particles will be discussed.
最近的实验研究表明，利用纸喷雾（PS）离子化技术，单颗粒悬浮方法可以有效地与质谱（MS）结合，用于皮升级液滴的成分分析。在这项工作中，我们研究了 PS-MS 对皮升级液滴中分析物的响应，探索了其对这些样品进行鉴定和定量的潜力。我们使用微滴分配器生成液滴，证明了对大气二次有机气溶胶中常见的含氧有机分子的一系列分析物具有灵敏度。我们评估了影响该方法重现性和灵敏度的实验因素，并探索了在含有单一组分或多组分分析物的液滴中，系统响应对分析物质量增加的线性关系。我们表明，多组分样品中分析物信号的比值可用于表征体系的相对组成。这些测量结果表明，液滴 PS-MS 方法是一种有效的工具，可用于对含有皮克级分析物的单个皮升级液滴进行定性和定量分析。还将讨论该技术在悬浮颗粒组成特征方面的潜在应用。
