Physicochemical-sensing electronic skin for stress response monitoring

A wearable stress response assessment system, comprising:

• a multilayer sweat sensor patch adapted to adhere to and induce sweat production from human skin, wherein the multilayer sweat sensor patch further comprises:
• a carbochol hydrogel-loaded sweat-stimulation electrode;
• a hydrogel-loaded sweat-stimulation electrode;
• three enzymatic biosensors;
• and
• three ion-selective sensors (ISEs);
• wherein the carbochol hydrogel-loaded sweat-stimulation electrode and the hydrogel-loaded sweat-stimulation electrode are integrated into a skin-interfaced laser-engraved microfluidic component, wherein the skin-interfaced laser-engraved microfluidic component collects an induced sweat sample for analysis;
• wherein the three enzymatic biosensors are integrated into a metabolite detection logical circuit that is further integrated within the sensor patch, wherein each enzymatic biosensor is configured to identify concentrations of one of glucose, lactate, and uric acid (UA) in the collected sweat sample;
• and
• wherein the three ion-selective sensors (ISEs) are integrated into a electrolyte detection logical circuit that is further integrated within the sensor patch, wherein each ion-selective sensor is configured to identify concentrations of one of Na+, K+, and NH4+ in the collected sweat sample;
• wherein the three enzymatic biosensors each comprise:
• an electrodeposited gold nanoparticles layer;
• an electrodeposited Prussian blue transduction layer;
• an electrodeposited nickel hexacyanoferrate (NiHCF) protection layer;
• and
• an enzyme layer in a glutaraldehyde-crosslinked bovine serum (BSA) matrix wherein the sweat sensor patch further comprises:
• a top layer fabricated through serial inkjet printing of silver and carbon;
• a bottom layer fabricated through serial inkjet printing of silver and carbon;
• and
• a middle polydimethylsiloxane (PDMS)-based airgap layer, wherein the middle polydimethylsiloxane (PDMS)-based airgap layer is spin-coated between the top and bottom layers
• wherein the three ion-selective sensors (ISEs) comprise:
• a carbon layer;
• and
• a polystyrene-block-poly (ethylene butylene)-block-polystyrene (SEBS)-polyvinyl chloride (PVC)/bis(2-ethylhexyl) sebacate (DOS)-ionophore/lipophilic anionic sites mixture based membrane layer.