Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7149883 | Sensors and Actuators B: Chemical | 2012 | 8 Pages |
Abstract
A novel ratiometric info-chemical communication system has been developed that is based upon an array of four surface acoustic wave (SAW) resonator microsensors operating at a frequency of 262Â MHz and under ambient conditions. The info-chemical mixtures were generated by a micro-evaporator and transported to the SAW sensors inside a flow chamber. Binary mixtures of 3-methylbutan-1-ol and ethyl acetate were used to demonstrate the principle of encoding and decoding different ratios of volatile info-chemicals in this system. The resonant frequencies of the four polymer-coated SAW sensors and the associated reference (uncoated) SAW sensors were used to determine differential responses corresponding to the different ratiometric mixtures of the info-chemicals. The SAW sensors were spray coated with four different stationary phase polymer compounds, namely polycaprolactone, polyvinylcarbazole, polystyrene-co-butadiene, and polyethylene-co-vinylacetate. Principal components analysis was performed on both steady-state and dynamic features extracted from the sensor responses. Our results show clear linear separability of the different chemical ratios as distinct clusters in multi-variate space. In conclusion, we believe that this is the first demonstration of the encoding, transmitting, and decoding ratiometric information using a system based upon an array of SAW-based microsensors. This novel info-chemical communication system, based upon fixed ratios, transmits chemical information over distances that would otherwise be impossible using absolute concentrations.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
J. Yang, Z. Rácz, J.W. Gardner, M. Cole, H. Chen,