Portable low-power electronic interface for gas detection using microcantilevers

Over the last decade, microcantilevers acting as chemical sensors have been demonstrated as a powerful technique for gas detection at trace level. However, one of the main limitations for a widespread deployment in commercial applications is due to the existing read-out technologies which are extremely slow and tedious. This paper presents the development of a portable low-power readout system to face with the throughput and reliability related challenges. In particular, the portable system is capable to generate the excitation signal and to acquire the output signal of resonating microcantilevers modified with zeolite based coatings for gas sensing applications. The accuracy of the read out system has been assessed by comparison with commercial lock-in amplifier 7265 model from Signal Recovery. The performance of the electronic interface has been validated in the detection of 25 ppmV of 2-nitrotoluene with BEA coated microcantilevers operating in dynamic mode.

[1]  Thomas Thundat,et al.  ReviewNanosensors for trace explosive detection , 2008 .

[2]  T. Thundat,et al.  Micro-differential thermal analysis detection of adsorbed explosive molecules using microfabricated bridges. , 2009, The Review of scientific instruments.

[3]  Isabelle Dufour,et al.  Zeolite-modified cantilevers for the sensing of nitrotoluene vapors , 2009 .

[4]  Antonio Gnudi,et al.  Integrated lock–in amplifier for sensor applications , 1999 .

[5]  Patrick Merken,et al.  Low-power lock-in amplifier for complex impedance measurement , 2009, 2009 3rd International Workshop on Advances in sensors and Interfaces.

[6]  Vincenzo Stornelli,et al.  Low-voltage low-power integrated analog lock-in amplifier for gas sensor applications , 2010 .

[7]  Isabelle Dufour,et al.  Detection of organic vapours with Si cantilevers coated with inorganic (zeolites) or organic (polymer) layers , 2012 .

[8]  J. Santamaría,et al.  Gas Sensing with Silicon-Based Nanoporous Solids , 2009 .

[9]  C. Vancura,et al.  Magnetically actuated complementary metal oxide semiconductor resonant cantilever gas sensor systems. , 2005, Analytical chemistry.

[10]  A. Hierlemann,et al.  Complementary metal oxide semiconductor cantilever arrays on a single chip: mass-sensitive detection of volatile organic compounds. , 2002, Analytical chemistry.

[11]  P H Sydenham,et al.  Phase sensitive detection as a means to recover signals buried in noise , 1975 .

[12]  N. Bârsan,et al.  Electronic nose: current status and future trends. , 2008, Chemical reviews.

[13]  G. G. Stokes "J." , 1890, The New Yale Book of Quotations.

[14]  B. Calvo,et al.  A 3V single supply LIA for portable sensing systems , 2011, 2011 IEEE SENSORS Proceedings.

[15]  Santiago Celma,et al.  Lock-in amplifier for portable sensing systems , 2011 .

[16]  Javier Sesé,et al.  Explosives detection using nanoporous coatings , 2011, Defense + Commercial Sensing.

[17]  M. L. Meade Lock-in amplifiers : principles and applications , 1983 .

[18]  E. Martinelli,et al.  A Fully-Analog Lock-In Amplifier With Automatic Phase Alignment for Accurate Measurements of ppb Gas Concentrations , 2012, IEEE Sensors Journal.

[19]  B. Rogers,et al.  Multifunctional self-sensing microcantilever arrays for unattended detection of chemicals, explosives, and biological agents , 2006, SPIE Security + Defence.

[20]  James K. Gimzewski,et al.  A chemical sensor based on a microfabricated cantilever array with simultaneous resonance-frequency and bending readout , 2001 .

[21]  J. Scofield Frequency‐domain description of a lock‐in amplifier , 1994 .

[22]  A. Boisen,et al.  Cantilever-like micromechanical sensors , 2011 .