Development of a Supramolecular-based Sensor for Rapid Detection of Ammonium Nitrate in Improvised Explosive Devices

Background: Ammonium nitrate (AN) is widely used in improvised explosive devices (IEDs) due to its accessibility and low cost. The surge in AN-based explosives in recent terror incidents across India necessitates the development of a reliable and rapid detection system, especially for on-site forensic investigations. Objective: To design and evaluate a supramolecular sensor based on a C cinnamaldehyde pyrogallol derivative that selectively detects ammonium nitrate through host–guest interaction, with potential application in counter-terrorism and forensic science. Methods: A novel supramolecular sensor was synthesised and characterised. Ultraviolet-visible (UV-Vis) spectroscopy and fluorescence spectroscopy were employed to monitor the interaction between AN and the sensor. Spectral shifts and intensity changes were analysed to confirm binding efficiency and selectivity. Results: The sensor exhibited potent and selective host–guest interactions with ammonium nitrate, producing a marked fluorescence enhancement upon binding. No significant interference was observed from other common nitrate-containing compounds. The sensor demonstrated high sensitivity, allowing detection of AN at trace concentrations. Conclusion: The developed supramolecular sensor provides a rapid, sensitive, and selective method for detecting ammonium nitrate. It holds promise for field-deployable forensic tools in explosive trace detection (ETD) and counter-terrorism applications.