Solpa Lee ^a,1, Minwoo Kim ^a,1, Bum Ju Ahn ^b, Yongwoo Jang ^a,b

^aDepartment of Medical and Digital Engineering, College of Engineering, Hanyang University, Seoul 04736, South Korea
^bDepartment of Pharmacology, College of Medicine, Hanyang University, Seoul 04736, South Korea

¹Solpa Lee (S. Lee) and Minwoo Kim (M. Kim) contributed equally to this work.
Correspondence to: Yongwoo Jang

Volatile organic compounds (VOCs) are gaseous chemicals found in ambient air and exhaled breath. In particular, highly reactive aldehydes are frequently found in polluted air and have been linked to various diseases. Thus, extensive studies have been carried out to elucidate disease-specific aldehydes released from the body to develop potential biomarkers for diagnostic purposes. Mammals possess innate sensory systems, such as receptors and ion channels, to detect these VOCs and maintain physiological homeostasis. Recently, electronic biosensors such as the electronic nose have been developed for disease diagnosis. This review aims to present an overview of natural sensory receptors that can detect reactive aldehydes, as well as electronic noses that have the potential to diagnose certain diseases. In this regard, this review focuses on eight aldehydes that are well-defined as biomarkers in human health and disease. It offers insights into the biological aspects and technological advances in detecting aldehyde-containing VOCs. Therefore, this review will aid in understanding the role of aldehyde-containing VOCs in human health and disease and the technological advances for improved diagnosis.