Determination of SOA peroxide content

Secondary organic aerosol particles (SOA) formed from the oxidation of monoterpenes can impact the Earth’s radiation balance, act as cloud condensation nuclei and negatively affect human health. In the initial Visiting Faculty Program application, we proposed the use of an ultraviolet-visible spectrometer equipped with a liquid waveguide capillary flow cell to determine the extent to which SOA absorb visible light. The inclusion of Concordia University in the Secondary Organic Aerosol From Forest Emissions Experiment (SOAFFEE) laboratory campaign at PNNL necessitated a change in the proposed experiments. An iodometricspectrophotometric (IS) technique was developed to quantify the total peroxide content in SOA. The experimental technique was validated by measuring the peroxide content in commercially available products. After the validation of the experimental technique, the total peroxide content of SOA formed from a variety of experimental conditions was quantified. It was found that the amount of peroxides in the SOA generated at PNNL was similar to that found in previous research studies. The research carried out at PNNL will be included in an undergraduate senior thesis at Concordia University Portland (CU). It is also expected that the research will be included in peer-reviewed journal articles. It is our hope that the success of our work will result in future collaborations between PNNL and CU. Determination of SOA peroxide content