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Organic Bio-electronic Sensors for Ultra-sensitive Chiral Differential Detection
Luisa Torsi, University of Bari "A. Moro", Italy
The energies involved in weak chiral interactions occurring between odorant binding proteins (OBPs) and carvone enantiomers are evaluated, down to a few KJ/mol, by means of a water-gated organic field-effect transistor (WGOFET) whose Au-gate is modified with a porcine-OBP (pOBP) self-assembled monolayer. The output current measured is dependent on the concentration of the analyte and pM concentrations can be detected. The binding curves also are significantly different between the two enantiomers. The modelling of the two curves allows the energies associated with the OBP-carvone complexes formation to be independently extracted, from the very same set of data. From the dissociation constants the standard free-energy the complex formation at the electrode is derived, while the threshold voltage shifts gives information on the electrostatic component. This approach, representing a unique tool to quantitatively investigate low-energy bio-chemical interactions, is rather general as it relies on the relative dielectric constants of the protein-SAMs and of the organic semiconductors being much lower than that of water. The role of the OBPs in the olfaction system is still under debate and the detection of neutral odorant species at the pM level by means of a WGOFET adds relevant pieces of information to the understanding of the odor perception mechanism at the molecular leve
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Biosignal-based Cognitive Systems and Applications
Tanja Schultz, Cognitive Systems Lab (CSL), University of Bremen, Germany
In the talk Tanja presented ongoing research at the Cognitive Systems Lab (CSL), where they explore human-centered cognitive systems to improve human-machine interaction as well as machine-mediated human communication. Several applications were described such as Silent Speech Interfaces that rely on articulatory muscle movement captured by electromyography to recognize and synthesize silently produced speech, as well as brain-computer interfaces that capture brain activity by electrocorticography to recognize speech and by electroencephalograhy to determine users' mental states, such as task activity, cognitive workload and attention.
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