Angew. Chem. Int. Edn doi:10.1002/anie.200804853 (2009)

Chemical hallmarks of certain explosives can be quickly identified by the loss of a characteristic glow in a very porous material.

The metal–organic framework (MOF) developed by Jing Li at Rutgers University in New Jersey and her colleagues is luminescent under ultraviolet light. But when its plentiful pores fill up with either 2,4-dinitrotoluene, a by-product of TNT manufacture, or 2,3-dimethyl-2,3-dinitrobutane (DMNB), a tracer molecule for plastic explosives, that luminescence fades.

This happens because the explosive molecules can quickly bind to the inside of the MOF, owing to its porosity, and once there they interfere with the electronic processes that otherwise cause luminescence.