Volatile-based ratiometric infochemical communication system using polymer-coated piezoelectric sensor arrays

In this paper we report upon the implementation and operation of a novel infochemical communication system that uses volatile components to encode, and polymer-coated piezoelectric sensors to decode ratiometric information. Blend information is generated in specific ratios of compounds by a micromachined mixer/evaporator module that is connected to a high-precision multi-channel syringe pump. Eight quartz crystal microbalances (QCM) and four dual surface acoustic wave (SAW) resonator sensors are used for blend detection. Ratiometric communication was demonstrated using seven different blend ratios at two concentrations of isoamyl alcohol and ethyl acetate. The receiver side of the system was able to classify the specific ratios of chemical compounds using simple multivariate data analysis, thus decoding the ratiometric information encoded by the emitter side.