Textile Wearable Organic Electrochemical Biosensors monitoring human psycho-physical condition

The issue to monitor human psycho-physical condition in noninvasive way, with wearable bio chemical sensor, through the real time test of physiological fluids, like sweat, need at least two strategic conditions to be realized. The first is that the device should be really warble and noninvasive, in a way that is not disturbing the daily life of the patients, and the second the device should absorb the fluids when they are produced. To reach this goal, we have realized electrochemical chemical sensor directly on a textile fiber of natural cotton. A specific functionalization allows to realize a device which is completely wearable and could not be felt by the user, and is able to naturally absorb the fluids to be tested, during any sports or physical activity. The device maintain flexibility, ease of preparation, low cost and biocompatibility [1]. Moreover it use a transistor architecture, which allows a high gain in transconductance and opens to different possible configuration measurements [2]. Here we applied conductive organic material on a natural textile surface, which as the property to be sensible to positive ions in the fluids, realizing a wearable electrochemical transistor. In particular, the cotton sensors have been used as monitor saline concentration in human sweat, to control dehydration of the patients [3]. Then a selective detection of specific molecules as neurotransmitters have been tested. Adrenaline has been selectively revealed respect to saline concentration. The sensing works through an oxidation process using nano-Pt electrode with formation adrenaline-quinone and then of adrenochrome [4]. The oxidation of adrenaline has been studied with UV-Visible absorbance in different conditions: in air, in presence of silver and of platinum working electrode Then, with a fine control of the reaction at the electrodes, using specific functionalization (enzymes), we revealed Tyrosine, Dopamine and Phenylalanine. The detection of human neurotransmitters allows to monitor and control psycho-physical condition, preventing critical conditions like panic or heart attack. With an in-situ and non-invasive approach, the selective biosensor monitor human performances (hydration and stress), could find large applications in sports, health care and working safety.