Nanomaterials-Enabled Sensors for Detecting and Monitoring Chemical Warfare Agents

Despite their restrictions under international treaties, many chemical warfare agents (CWAs) and their toxic analogues are still used in various industrial sectors such as agriculture and chemical manufacturing. Thus, the need for sensitive and selective CWA detection remains critical. Commercially available detection methods, while accurate, are often bulky, expensive, and require specialized personnel. Sensors incorporating nanomaterials present a promising alternative, offering rapid, portable, and cost-effective detection due to their unique properties, such as high surface area and tunable reactivity. This review covers the four main CWA categories: nerve agents, blister agents, blood agents, and choking agents, highlighting recent progress in nanosensor development for each category. It discusses various sensing mechanisms employed, including fluorescence, colorimetry, chemiresistivity, electrochemistry, and Raman spectroscopy. Despite these advancements, challenges remain, particularly regarding the scalability, stability, and selectivity of nanomaterials-based sensors in complex environments. The review concludes by emphasizing the need to address these challenges and explore novel nanomaterials, the development of scalable nanomanufacturing techniques, and the integration of artificial intelligence to fully unlock the potential of nanomaterials in CWA sensing for homeland security and personal safety.