Continuous ion beam-induced luminescence (IBIL) spectroscopy of air-borne particulate matter hourly collected from the atmosphere

We investigated the applicability of Ion Beam Induced Luminescence (IBIL) analysis for identifying biological components in sequentially collected airborne particulate matter (PM) samples obtained using the automated sampler. A series of micro-IBIL spectroscopies were performed on a PTFE (polytetrafluoroethylene) membrane tape filter from the Atmospheric Environmental Regional Observation System (AEROS) during a highly concentrated air pollution event on 26–27 March 2020, collected at Ota, Japan (36.290°n, 139.381°e) using an external 3 MeV proton microprobe. IBIL at typical wavelengths associated with organic compounds such as NADH and riboflavin were identified through the series of IBIL analyses, which is a key factor for identifying existence of organic pollutions, or bioaerosols. The decay times of the IBIL indicate that the peak measured is due to organic compounds rather than inorganic particles or ambient substances. These results suggest that micro-IBIL spectroscopy can be used to identify bioaerosols in hourly collected AEROS PTFE membrane tape filters taken from the atmosphere.