Systems and methods for identifying explosives

A system for identifying an explosive, the system comprising a substrate carrying a plurality of sensing devices, each sensing device comprising at least one semiconductor nanostructure having attached thereto a functional moiety selected to interact with an explosive-containing sample, wherein each sensing device is configured to generate a detectable signal responsively to said interaction, and wherein at least two different sensing devices comprise different functional moieties, and

• a signal processor having a circuit configured to extract, from each generated signal, a kinetic parameter describing a respective interaction of said sample with a respective sensing device, thereby to construct an explosive fingerprint indicative of said explosive, said explosive fingerprint being defined as a set of kinetic parameters, at least one parameter for each sensing device, wherein said kinetic parameter comprises a ratio between a first parameter which is slope describing rise of a respective signal and a second parameter which is a slope describing a descent of said respective signal;
• wherein at least one of said sensing device comprises a plurality of semiconductor nanostructures, and is configured to generate a group of signals, a signal for each of at least a portion of said plurality of nanostructures, and wherein said signal processor is configured to extract said kinetic parameter collectively from said group of signals, and
• wherein said signal processor is configured to extract pairs of parameters from each signal of said group of signals, thereby to provide a plurality of pairs of parameters, and to calculate said kinetic parameter by fitting said plurality of pairs of parameters to a predetermined fitting function.