A sensitive, handheld vapor sensor based on microcantilevers

We report the development of a handheld sensor based on piezoresistive microcantilevers that does not depend on optical detection, yet has high detection sensitivity. The sensor is able to detect vapors from the plastic explosives pentaerythritol tetranitrate and hexahydro-1,3,5-triazine at levels below 10 parts per trillion within few seconds of exposure under ambient conditions. A differential measurement technique has yielded a rugged sensor that is unaffected by vibration and is able to function as a “sniffer.” The microelectromechanical system sensor design allows for the incorporation of hundreds of microcantilevers with suitable coatings in order to achieve sufficient selectivity in the future, and thus could provide an inexpensive, unique platform for the detection of chemical, biological, and explosive materials.

[1]  Dmitrii V. Tchekhovskoi,et al.  The critical evaluation of a comprehensive mass spectral library , 1999, Journal of the American Society for Mass Spectrometry.

[2]  J Michael Ramsey,et al.  Analysis of volatile organic compounds in air with a micro ion trap mass analyzer. , 2003, Analytical chemistry.

[3]  Thomas Thundat,et al.  Nerve agents detection using a Cu2+/L-cysteine bilayer-coated microcantilever. , 2003, Journal of the American Chemical Society.

[4]  J Thaysen,et al.  Optimised cantilever biosensor with piezoresistive read-out. , 2003, Ultramicroscopy.

[5]  J. Grate.  Acoustic wave microsensor arrays for vapor sensing. , 2000, Chemical reviews.

[6]  F. McLafferty,et al.  Unknown identification using reference mass spectra. Quality evaluation of databases , 1999, Journal of the American Society for Mass Spectrometry.

[7]  J. Thaysen,et al.  Environmental sensors based on micromachined cantilevers with integrated read-out , 2000, Ultramicroscopy.

[8]  D. Rounbehler,et al.  Vapor pressure of explosives , 1986 .

[9]  T. Thundat,et al.  Sensitive detection of plastic explosives with self-assembled monolayer-coated microcantilevers , 2003 .

[10]  Thomas Thundat,et al.  Thermal and ambient-induced deflections of scanning force microscope cantilevers , 1994 .

[11]  George G. Guilbault,et al.  Commercial quartz crystal microbalances-Theory and applications , 1999 .

[12]  C. Quate,et al.  Atomic resolution with an atomic force microscope using piezoresistive detection , 1993 .