Imaging a Smell

Abstract

An electronic tongue or nose device (eT/eN) is an assembly of non-specific sensors. The information given by each sensor is complementary and the combination of all sensors' results generates a unique fingerprint. Our team has developed a new paradigm based on a combinatorial approach to simplify greatly the preparation of sensing materials for constructing e-noses/tongues. Instead of designing and synthesizing a large number of differential receptors, that often represents a laborious and time-consuming task, we prepared an array of combinatorial assemblies behaving as cross-reactive receptors by self-assembly of a handful of building blocks (BBs: small and easily accessible molecules with different physicochemical properties) mixed in varying and controlled proportions. By combining such an array with a real-time optical detection system such as Surface Plasmon Resonance imaging (SPRi), the obtained eT is capable of generating 3D continuous evolution patterns just like vivid landscapes for each sample. The same approach is currently developed to sense gas and VOCs on an SPRi bearing more than 40 sensors opening a new approach for e-nose design.