Detection of triacetone triperoxide (TATP) with an array of sensors based on non-specific interactions

An array of hybrid organic-semiconductor sensors was developed aimed at selectively detecting triacetone triperoxide (TATP). Each element of the array is a field effect-like transistor based on GaAs. The gate in these devices has been replaced by a self-assembled monolayer of receptor molecules. The current layout features selectivity to TATP and is able to detect less than 100 ppb. A correlation among the responses, the chain length of the grafted molecules, and the surface potential is exhibited, suggesting that the sensing mechanism involves charge transfer between the adsorbed molecules and the substrate.