Enhanced Discrimination of Complex Odours Based upon Spatio-Temporalsignals from a Micro-Mucosa

We recently reported the novel concept of an artificial olfactory mucosa based upon a set of sensor clusters distributed along a channel coated with a retentive layer. Such a system generates complex signals containing both spatial information (i.e. response magnitude) based upon different types of sensors and temporal information (i.e. delay time like in a GC) based upon retention time differences between identical sensors. Here we report on the development of a micro artificial mucosa or micro e-mucosa. The microsystem comprises of a silicon microsensor array coupled to a true 3D micro-fluidic package fabricated by micro-stereolithography. Results show a differential temporal delay of 96 seconds between simple odours (pulses of toluene and ethanol vapour in air) and improved discrimination of complex odours by combining temporal with spatial data. We believe that this new micro e-mucosa offers a significant advance in the field of machine olfaction.