A fluorescence turn-on mechanism to detect high explosives RDX and PETN.

Detecting hidden explosive devices in war zones and transportation hubs is a pressing concern. Current efforts have focused on sensing three commonly used powerful explosives: 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX) and pentaerythritol tetranitrate (PETN) (Chart 1). The need for ultratrace detection of these low-volatility compounds has resulted in an intense interest in fluorescence methods, and the direct detection of TNT vapor by amplifying fluorescent polymers is now an established technology.1 However analogous examples of direct RDX or PETN detection are sparse, and current methods rely heavily on ion mobility spectrometry,2a mass spectrometry,2b and, to a lesser extent, detecting either chemically modified RDX3a or its degradation products.3b Herein we present an advance based on a molecular chemosensor (1) for the direct fluorescent detection of RDX and PETN.