Developing Novel Analytical Systems for Deciphering Complex Mixtures of Organic Compounds and Training the Next Generation of Scientists

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This project is focused on developing methods for identifying and characterizing specific organic compounds or classes of compounds in a complex mixture of organics in the atmosphere. A large array of sophisticated analytical techniques and instrumentation will be used in the laboratory for optimal characterization of atmospheric gases and aerosols. Understanding the complex composition of gas and particle phase constituents is critically important for air quality studies, especially with regards to determining the toxicity of the inhaled components. The project includes support for graduate and undergraduate students to participate in the research. The project will also involve high school students from the EVOLUTIONS program. The goal of EVOLUTIONS is to supplement the formal school experiences of underserved students to develop transferable skills, STEM literacy, college preparation, and foster aspirations for STEM futures.This proposal involves methods development for offline analytical GC x MS-MS and LC x MS-MS techniques to improve characterization of compound classes that are difficult to measure using online techniques. Laboratory studies will be used to evaluate various analytical configurations for optimal characterization of classes of organics present in atmospheric aerosols, many that are likely important for the characterization of organic aerosol sources and atmospheric processing. In Task 1, an atmospheric pressure chemical ionization (APCI) source and a secondary electrospray ionization (SESI) source will be integrated with an Agilent GC x MS-MS. Method development will be employed to improve thermal extraction of intermediate volatility/ semi-volatile organic carbon (I/SVOCs) collected on adsorbent tubes. Task 2 is focused on LC x MS-MS method development, with specific focus on improving solvent extraction of highly oxygenated molecules (HOM) species collected on adsorbent tubes. Task 3 will intercompare results for target analytes (e.g. I/SVOCs, HOMs, organic nitrates) with an online ToF-CIMS. This work has the potential to contribute new insight to organic aerosol characterization, especially with regards to the intercomparison studies with ToF-CIMS.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.