DESCRIPTION:

In this invention, core-shell nanoparticles are assembled as thin films on quartz crystal microbalance and interdigitated microelectrode sensor devices via controlled interparticle molecular linkers involving inter-shell hydrogen-bonding or covalent bonding.  The different nanostructured components are used as chemoselective array sensing probes with extremely high response sensitivity and selectivity to nitroaromatic vapors. 

A detection limit of <1 ppt is found for TNT-related explosive vapors.  Because of the high selectivity and low detection limit, and stability of the nanostructured array elements, the technology is versatile for fabricating portable sensor devices for field and remote sensing applications.  Laboratory scale production of the sensing materials has been achieved, and prototype sensor devices are available for testing.

ADVANTAGES:

In comparison with other sensor technologies such as polymers coated on SAW devices [3], or nanoparticles evaporated on IME devices [4], this technology offers an array of fine-tunable and stable sensing probes with high sensitivity, selectivity, and reproducibility, longer duration time and low detection limit. Importantly, the sensitivity of the nanostructured sensing materials to TNT-related explosive nitroaromatic vapors can reach sub ppt level. The device can be easily miniaturized into portable format, and is applicable to remote and in-situ detection of explosive vapors and land mines, and different security inspection settings.

DISADVANTAGES:

None

PATENT STATUS:

Patent application is being finalized