Advancing Breath Biomarker Detection with Chemiresistive Metal Oxide Nanostructures: A Pathway to Next‐Generation Diagnostic Tools

Abstract Breath biomarker detection represents a transformative frontier in non‐invasive diagnostics, offering rapid, real‐time insights into health conditions ranging from metabolic disorders to cancer. Metal oxide nanostructures (MONs) have emerged as key materials in this research because of their large surface area, adjustable electrical characteristics, and sensitivity to gaseous biomarkers at trace quantities. This paper examines current advances in chemiresistive MON‐based sensors, focusing on the importance of structural optimization, hybrid material systems, and functionalization strategies in improving performance. Exploring the study of complicated datasets, the prediction of biomarker signatures, and dynamic aims in tuning the quality of the sensors. Functionalization strategies also play a vital role in enhancing the performance of MON‐based sensors. By modifying the surface chemistry of chemiresistive metal oxides, researchers can tailor the sensors to preferentially adsorb certain gaseous biomarkers while minimizing interference from other compounds present in breath. Future opportunities include the development of multimodal sensors, simplified and portable devices, and durable, reusable platforms capable of long‐term operation in real‐world environments. With the confluence of nanotechnology and data‐driven analytics, MON‐based breath sensors have the potential to transform customized healthcare by providing worldwide early detection, illness monitoring, and preventative medication.