Flexible and stretchable electronic systems for epidermal electronics

Abstract

Provided herein are skin-mounted biomedical devices and methods of making and using biomedical devices for sensing and actuation applications. For example, flexible and/or stretchable biomedical devices are provided, including electronic devices useful for establishing conformal contact with the skin of a subject. Devices disclosed herein can comprise a plurality of sensing and/or actuating devices provided as part of a skin-mounted flexible or stretchable electronic circuit.

1 - 89 . (canceled) 
     
     
         90 . A device for establishing an interface with a skin of a subject, the device comprising:
 a flexible substrate having an effective Young's modulus less than or equal to 10 GPa;   a flexible electronic circuit supported by the flexible substrate, wherein the flexible electronic circuit comprises a plurality of electrophysiological sensors connected with filamentary wires; each of the electrophysiological sensors independently comprising an inorganic layer, an electrode layer, or both, including one or more inorganic semiconductor circuit elements or electrodes, or a combination of inorganic semiconductor circuit elements and electrodes; and   a barrier layer encapsulating at least a portion of the flexible electronic circuit, the barrier layer being a multilayer structure comprising a plurality of layers, the barrier layer providing one or more of an electrical, physical, chemical, biological, or thermal barrier,   wherein the device has a multilayer geometry including the flexible substrate, the flexible electronic circuit, and the barrier layer as a series of stacked layers with the flexible electronic circuit provided between the flexible substrate and the barrier layer, and   wherein the flexible substrate, barrier layer and the electronic circuit provide a net bending stiffness allowing conformal contact to be established with the skin of the subject.   
     
     
         91 . The device of  claim 90 , wherein the barrier layer is patterned so as to selectively modulate one or more of physical contact, thermal contact, chemical contact, biological contact, optical communication, or electrical communication between the flexible electronic circuit and the skin. 
     
     
         92 . The device of  claim 90 , wherein the barrier layer is patterned to provide one or more transparent regions, wherein the transparent regions transmit to or from the flexible electronic circuit ultraviolet, visible or near-infrared electromagnetic radiation having a preselected wavelength distribution. 
     
     
         93 . The device of  claim 90 , wherein the barrier layer is patterned to provide one or more opaque regions that substantially prevent transmission to or from the flexible electronic circuit of electromagnetic radiation having a preselected distribution of wavelengths in the ultraviolet, visible or near-infrared regions of the electromagnetic spectrum. 
     
     
         94 . The device of  claim 90 , wherein the barrier layer is patterned to provide one or more permeable regions that are selectively permeable to one or more target molecules to allow transport of the target molecules from the skin to the flexible electronic circuit or from the flexible electronic circuit to the skin. 
     
     
         95 . The device of  claim 90 , wherein the barrier layer is patterned to provide one or more impermeable regions that are impermeable to one or more target molecules to prevent transport of the target molecules from the skin to the flexible electronic circuit or from the flexible electronic circuit to the skin. 
     
     
         96 . The device of  claim 90 , further comprising a controller in communication with the flexible electronic circuit, the controller configured to receive input signals from the flexible electronic circuit and provide output signals to the flexible electronic circuit, wherein the controller receives and analyzes input signals corresponding to one or more measurements from one or more of the plurality of electrophysiological sensors and generates output signals that control or provide one or more sensing or actuation parameters to the flexible electronic circuit. 
     
     
         97 . The device of  claim 90 , wherein the flexible substrate comprises one or more of a polymer, an inorganic polymer, an organic polymer, a plastic, an elastomer, a biopolymer, a thermoset, rubber, fabric, paper, or any combinations thereof. 
     
     
         98 . A device for establishing a conformal interface with a skin of a subject, the device comprising:
 a flexible substrate;   a flexible electronic circuit supported by the flexible substrate, the flexible electronic circuit comprising a plurality of hydration sensors for determining hydration of underlying skin of the subject, each hydration sensor independently comprising an inorganic layer, an electrode layer, or both, including one or more semiconductor circuit elements or electrodes, the plurality of hydration sensors being connected with filamentary wires; and   a barrier layer encapsulating at least a portion of the flexible electronic circuit, the barrier layer including a plurality of layers, the barrier layer providing an electrical, physical, chemical, biological or thermal barrier,   wherein the flexible substrate, the flexible electronic circuit, and the barrier layer are provided as a series of stacked layers with the flexible electronic circuit provided between the flexible substrate and the barrier layer, and   wherein the flexible substrate, barrier layer and the electronic circuit provide a net bending stiffness allowing conformal contact to be established with the skin of the subject.   
     
     
         99 . The device of  claim 98 , wherein the flexible substrate comprises one or more of a polymer, an inorganic polymer, an organic polymer, a plastic, an elastomer, a biopolymer, a thermoset, rubber, fabric, paper, or any combinations thereof. 
     
     
         100 . The device of  claim 98 , wherein the plurality of hydration sensors include an electrode for determining the impedance of underlying skin. 
     
     
         101 . The device of  claim 98 , wherein the plurality of hydration sensors include one or more LEDS and photodiodes for determining the water absorption of underlying skin. 
     
     
         102 . The device of  claim 98 , wherein the barrier layer is patterned to provide one or more transparent regions, wherein the transparent regions transmit to or from the flexible electronic circuit ultraviolet, visible or near-infrared electromagnetic radiation having a preselected wavelength distribution. 
     
     
         103 . The device of  claim 98 , wherein the barrier layer is patterned to provide one or more opaque regions that substantially prevent transmission to or from the flexible electronic circuit of electromagnetic radiation having a preselected distribution of wavelengths in the ultraviolet, visible or near-infrared regions of the electromagnetic spectrum. 
     
     
         104 . The device of  claim 98 , wherein the barrier layer is patterned to provide one or more permeable regions that are selectively permeable to one or more target molecules to allow transport of the target molecules from the skin to the flexible electronic circuit or from the flexible electronic circuit to the skin. 
     
     
         105 . The device of  claim 98 , wherein the barrier layer is patterned to provide one or more impermeable regions that are impermeable to one or more target molecules to prevent transport of the target molecules from the skin to the flexible electronic circuit or from the flexible electronic circuit to the skin. 
     
     
         106 . The device of  claim 98 , further comprising a controller in communication with the flexible electronic circuit, the controller configured to receive input signals from the flexible electronic circuit and provide output signals to the flexible electronic circuit, wherein the controller receives and analyzes input signals corresponding to one or more measurements from said one or more hydration sensors and generates output signals that control or provide one or more sensing or actuation parameters to the flexible electronic circuit. 
     
     
         107 . A device for establishing a human-to-machine interface with a skin of a subject, the device comprising:
 a flexible substrate;   a flexible electronic circuit supported by the flexible substrate, wherein the flexible electronic circuit comprises a plurality of electrophysiological sensors; wherein each of said electrophysiological sensors independently comprises an inorganic layer, an electrode layer or a combination of these; including one or more inorganic semiconductor circuit elements or electrodes, or a combination of inorganic semiconductor circuit elements and electrodes, wherein the plurality of electrophysiological sensors are connected with filamentary wires; and   a barrier layer encapsulating at least a portion of the flexible electronic circuit; wherein said barrier layer is a multilayer structure comprising a plurality of layers; wherein said barrier layer provides an electrical, physical, chemical, biological or thermal barrier; said device having a multilayer geometry wherein said flexible substrate, said flexible electronic circuit and said barrier layer are provided as a series of stacked layers wherein said flexible electronic circuit is provided between said flexible substrate and said barrier layer;   wherein the flexible substrate, barrier layer and the electronic circuit provide a net bending stiffness so as to allow for conformal contact to be established with the skin of the subject.   
     
     
         108 . The device of  claim 107 , wherein at least one of the plurality of electrophysiological sensors is configured to provide signals corresponding to muscle activity. 
     
     
         109 . The device of  claim 107 , wherein at least one of the plurality of electrophysiological sensors is configured to provide signals corresponding to an acceleration of the skin or a movement of the skin. 
     
     
         110 . The device of  claim 107 , wherein at least one of the plurality of electrophysiological sensors is configured to provide signals corresponding to a change in the concentration of a target molecule at the skin.