Comparison of Different Vibrational Spectroscopic Probes (ATR-FTIR, O-PTIR, Micro-Raman, and AFM-IR) of Lipids and Other Compounds Found in Environmental Samples: Case Study of Substrate-Deposited Sea Spray Aerosols.

The use of vibrational spectroscopy to probe environmental samples is increasing with the development of new methods, including microspectroscopic probes. In this study, we compare different vibrational methods to interrogate lipids and other compounds found in environmental samples. In particular, we compare the vibrational spectra for different lipids that include fatty acids (protonated and deprotonated forms), fatty alcohols, and fatty esters by utilizing attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, optical photothermal infrared (O-PTIR) spectroscopy, micro-Raman spectroscopy, and atomic force microscopy infrared (AFM-IR) spectroscopy.

Photoinitiated Degradation Kinetics of the Organic UV Filter Oxybenzone in Solutions and Aerosols: Impacts of Salt, Photosensitizers, and the Medium.

Organic UV filters like oxybenzone (BP3) in sunscreens are seawater pollutants suspected to transfer to the atmosphere via sea spray aerosol (SSA). This study examines the photoinitiated degradation of BP3 in artificial and real seawater compared to SSA mimics containing NaCl and 4-benzoylbenzoic acid (4-BBA). We investigated pure, binary, and ternary mixtures of BP3, NaCl, and 4-BBA using solar-simulated light to isolate the effects of salt and photosensitization on BP3 degradation.