MRI: Development of a Chemical Ionization Time-of-Flight Mass Spectrometer for On-line Organic Aerosol Analysis

该奖项由2009年美国复苏和再投资法案(公法111-5)资助。该项目将开发一种新型的化学电离气溶胶飞行时间质谱仪(CI-ATOFMS)，它将结合CI的软和选择性电离、电动离子漏斗(IF)的离子捕获和传输特性以及高分辨率正交加速飞行时间(OA-TOF)质谱仪，以生产一种用于表征大气气溶胶有机含量的高灵敏度和选择性仪器。新仪器将补充现有的测量方法，同时对导致气溶胶中存在的各种有机物种的来源和过程提供独特的见解。CI-ATOFMS的分析能力包括：1)获得单个颗粒中有机物种的实时信息；2)提供表面与整体物种的信息；以及3)选择性地分析特定类别的化合物。能够确定单一气溶胶颗粒的有机含量，并根据气溶胶的来源、年龄和/或混合状态将其进一步分类，这将使了解气溶胶对健康和环境的影响迈出变革性的一步。除了大气化学，对复杂的小混合物进行灵敏的在线CI质谱分析将为单细胞、水和空气中的颗粒(即病毒、浮游植物、细菌)、药粉、纳米材料以及霉菌和花粉等过敏原的分析打开新的大门。在线分析的另一个好处是样品制备最少，高通量和化合物的快速筛选，这些都是制药工业、有机和生化合成、早期癌症筛查和疾病检测、在线单细胞蛋白质组学和生物质谱学的当前需求。这个仪器开发项目的工作将为研究生、博士后研究员和本科生提供独特的经验，因为仪器是设计、制造和测试的。从分析化学的角度来看，学生将接受使用最先进的仪器和计算工具进行复杂混合物的分析和去卷积的培训。首席调查员小组的所有成员都积极参与宣传方案，教育公众，他们定期参加大学和社区的宣传活动。在夏季，该组织接待参加加州大学圣地亚哥分校研究项目的本科生，这些项目专门服务于代表不足的少数族裔(非洲裔美国人、奇卡诺人、拉美人、美洲原住民和太平洋岛民)，主修化学、物理或其他科学。此外，新开发的仪器将通过斯克里普斯海洋研究所的桦树水族馆进行的公共宣传活动得到广泛曝光，该水族馆每年接待约40万游客。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This project will develop a novel chemical ionization aerosol time-of-flight mass spectrometer (CI-ATOFMS) that will couple the soft and selective ionization of CI, the ion trapping and transfer properties of an electrodynamic ion funnel (IF), and a high resolution orthogonal acceleration time-of-flight (oa-TOF) mass spectrometer to produce a highly sensitive and selective instrument for characterizing the organic content of atmospheric aerosols. The new instrument will complement existing measurement methods while providing unique insights into the sources and processes leading to the large variety of organic species that exist in aerosols. The analytical capabilities of CI-ATOFMS include: 1) obtaining real-time information on organic species in individual particles; 2) providing information on surface versus bulk species; and 3) selectively analyzing specific classes of compounds. The ability to identify the organic content of single aerosol particles and further classify the aerosols into broad categories based on their source, age, and/or mixing state will make possible a transformative step towards understanding the impact of aerosols on health and the environment. Beyond atmospheric chemistry, performing sensitive on-line CI mass spectrometry on small complex mixtures will open new doors for the analysis of systems such as single cells, particles in water and air (i.e., viruses, phytoplankton, bacteria), pharmaceutical powders, nanomaterials, and allergens such as mold and pollen. On-line analysis has the added benefit of minimal sample preparation, high throughput and rapid screening of compounds, which are current needs in the pharmaceutical industry, organic and biochemical synthesis, early-cancer screening and disease detection, on-line single cell proteomics, and biological mass spectrometry. Working on this instrument development project will provide unique experiences to graduate students, postdoctoral fellows, and undergraduates as the instrument is designed, built, and tested. From an analytical chemistry perspective, students will be trained in the analysis and deconvolution of complex mixtures using state-of-the-art instrumentation and computational tools. All members of the principal investigator's group are proactive in outreach programs to educate the public and they participate regularly in university and community outreach activities. During the summers, the group hosts undergraduates who participate in research programs at the University of California, San Diego that specifically serve underrepresented minorities (African Americans, Chicanos, Latinos, Native Americans, and Pacific Islanders) majoring in chemistry, physics, or other sciences. In addition, the newly developed instrument will receive extensive exposure through public outreach efforts run through the Birch Aquarium at Scripps Institution of Oceanography, which hosts approximately 400,000 visitors per year.