Innovations in Electrochemical Sensors for TNT Explosive Detection: From Nanomaterials to Wearable Devices and...

The detection of explosive residues, particularly nitroaromatic compounds such as 2,4,6-trinitrotoluene (TNT), is a major global concern because of their threats to security, public health, and environmental safety. TNT is highly toxic, chemically stable, and environmentally persistent, creating an urgent demand for sensitive, selective, and reliable detection strategies. Conventional analytical methods are effective but remain expensive, time-consuming, non-portable, and dependent on sophisticated instrumentation and trained personnel. Electrochemical sensing has emerged as a promising alternative due to its rapid response, high sensitivity, portability, low cost, and minimal sample-preparation requirements. However, conventional electrodes often exhibit limited surface area and poor electrochemical activity, thereby reducing performance in complex matrices. Recent advances in nanomaterials, including metal nanoparticles, carbon nanomaterials, metal-organic frameworks, and conductive polymers, have significantly enhanced electron transfer, analyte recognition, sensitivity, selectivity, and detection limits. This review critically evaluates recent advances in electrochemical sensors for TNT detection, emphasizing real-sample performance, nanomaterial integration for enhanced sensitivity and selectivity, portable and wearable field platforms, and the growing role of artificial intelligence in improving the detection accuracy. In addition, wearable and AI-assisted sensing platforms enable real-time monitoring, improved signal interpretation, and more reliable identification of TNT residues under diverse environmental and operational conditions during emergencies.