Amino Acid and Amine Compounds in Fine Aerosol Particles: A Review of Determination Methods, Abundances, Origins, and Atmospheric Processes

Abstract

Amino acid and amine compounds in aerosols are typical reduced nitrogen-containing organic compounds. These species originate from diverse natural and anthropogenic sources, including terrestrial and marine emissions and agricultural and industrial activities. Moreover, aerosol amino acid and amine compounds can also be produced through secondary processes in the atmosphere. Their chemical diversity and reactivity significantly impact the formation of aerosols, the physicochemical properties of aerosols, cloud formation, nutrient cycling, climate dynamics, and public health. Advanced analytical techniques, such as high-resolution mass spectrometry and isotopic analysis, have enabled detailed characterization and improved our understanding of their compositions, abundances, origins, atmospheric transformations, and environmental impacts. However, the evolution of chemical analytical methodologies has also led to the generation of data that is no longer directly comparable. This review discusses various detection methods of the amino acid and amine compounds in fine aerosol particles, attempting to provide scientific references for future unified optimal detection methods. Subsequently, the compositions and abundances in different atmospheric environments (i.e., urban, suburban, rural, and background environments) were summarized and compared. Further discussion on the potential origins and atmospheric chemical processes of the amino acid and amine compounds indicates that their diverse sources and atmospheric transformation are the key factors leading to fluctuations in their composition and abundance. The overall review is expected to provide a framework or data reference for future research in this rapidly evolving field.