SnO2 nanostructure-based acetone sensors for breath analysis

Abstract The World Health Organization reports that metabolic disorders are responsible for a significant proportion of global mortality. Considering this, breath sensors have gained prominence as effective tools for monitoring and diagnosing metabolic disorders, thanks to recent advancements in science and technology. In human exhaled breath, over 870 distinct volatile organic components (VOCs) have been identified. Among several VOCs, the detection of acetone in exhaled breath has received considerable attention in biomedical applications. Research indicates a strong correlation between high acetone levels in human breath and several diseases, such as asthma, halitosis, lung cancer, and diabetes mellitus. For instance, acetone is particularly noteworthy as a biomarker in diabetes, where its concentration in exhaled breath often surpasses 1.76 parts per million (ppm), compared to less than 0.8 ppm in healthy individuals. Early diagnosis and intervention in diseases associated with elevated acetone levels, aided by such non-invasive techniques, have the potential to markedly reduce both mortality and the financial burden of healthcare. Over time, various nanostructured gas sensing technologies have been developed for detecting acetone in both ambient air and exhaled breath. This article presents a mini review of cutting-edge research on acetone gas sensing, focusing specifically on nanostructured metal oxides. It discusses critical factors influencing the performance of acetone gas sensors, including acetone concentration levels and operational temperature, which affect their sensitivity, selectivity, and response times. The aim of this review is to encourage further advancements in the development of high-performance acetone gas sensors utilizing nanostructured materials, contributing to more effective management of metabolic disorders.