Wearable device for sensing biofluids

Abstract

The invention addresses confounding difficulties involving continuous sweat analyte measurement. Specifically, the present invention provides: at least one component capable of monitoring whether a sweat sensing device is in sufficient contact with a wearer's skin to allow proper device operation; at least one component capable of monitoring whether the device is operating on a wearer's skin; at least one means of determining whether the device wearer is a target individual within a probability range; at least one component capable of generating and communicating alert messages to the device user(s) related to: wearer safety, wearer physiological condition, compliance with a requirement to wear a device, device operation; compliance with a behavior requirement, or other purposes that may be derived from sweat sensor data; and the ability to utilize aggregated sweat sensor data that may be correlated with information external to the device to enhance the predictive capabilities of the device.

What is claimed is: 
     
         1 . A device, comprising:
 a flexible substrate configured to conform to skin, wherein a the flexible substrate includes a microfluidic component for transporting a biofluid; and   one or more sensors supported by the flexible substrate, wherein at least one of the one or more sensors is configured to obtain one or more time-resolved measurements of the biofluid.   
     
     
         2 . The device of  claim 1 , wherein the one or more time-resolved measurements include a concentration of one or more analytes of the biofluid. 
     
     
         3 . The device of  claim 2 , wherein the one or more analytes includes ions, electrolytes, small molecules, and/or metabolites. 
     
     
         4 . The device of  claim 1 , wherein the one or more time-resolved measurements includes a rate in which the biofluid is being produced. 
     
     
         5 . The device of  claim 1 , wherein the one or more time-resolved measurements includes a ratio of concentrations of two or more analytes of the biofluid. 
     
     
         6 . The device of  claim 1 , wherein a first sensor of the one or more sensors is configured to measure a first concentration of an analyte of the biofluid, and second sensor of the one or more sensors is configured to measure a second concentration of the analyte of the biofluid. 
     
     
         7 . The device of  claim 1 , wherein the flexible substrate includes an adhesive layer configured to be removably adhered to skin. 
     
     
         8 . The device of  claim 1 , wherein each time resolved measurement of the one or more time-resolved measurements is obtained at a predetermined time instance or over a predetermined time interval. 
     
     
         9 . The device of  claim 1 , wherein the flexible substrate includes a plurality of pores to allow passage of the biofluid from the skin to the one or more sensors. 
     
     
         10 . The device of  claim 1 , further comprising:
 a vapor-porous cover.   
     
     
         11 . The device of  claim 1 , wherein the flexible substrate includes one or more of a metal, a polyimide, a Kapton™, and a polyurethane. 
     
     
         12 . The device of  claim 1 , wherein the device is configured to detect, monitor, and/or characterize the biofluid. 
     
     
         13 . The device of  claim 1 , wherein the one or more sensors include one or more of: an electrochemical sensor, an ion-selective electrode sensor, a temperature sensor, a sweat rate sensor, a potentiometric sensor, an amperometric sensor, an impedimetric sensor, a capacitive sensor, an optical sensor, a chem-FET sensor, an accelerometer, a mechanical sensor, a heart rate monitor, a galvanic skin response sensor, a pulse oximetry sensor, or combinations thereof. 
     
     
         14 . The device of  claim 1 , further comprising a transmitter, a receiver, or a transceiver. 
     
     
         15 . The device of  claim 1 , further comprising a near field communication antenna coil, a radio frequency identification antenna coil, or a Bluetooth transceiver. 
     
     
         16 . The device of  claim 1 , wherein the biofluid is sweat. 
     
     
         17 . The device of  claim 1 , wherein the device has a length selected from a range of 40 millimeters to 60 millimeters, a width selected from a range of 25 millimeters to 70 millimeters, and a thickness selected from a range of 1.2 millimeters to 2 millimeters. 
     
     
         18 . The device of  claim 1 , wherein a plurality of microfluidic channels are connected to a plurality of biofluid collectors via a plurality of dissolvable gates, and wherein the device is configured to collect discrete samples of the biofluid at one or more predetermined time instances or over one or more predetermined time intervals. 
     
     
         19 . A method, comprising:
 providing a device for analyzing a biofluid, the device comprising:
 a substrate for mounting on a surface; and 
 one or more sensors supported by the substrate, wherein the substrate is configured to transport the biofluid from the surface to the one or more sensors, and wherein the device, using the one or more sensors, characterizes one or more temporal properties of the biofluid 
   mounting the substrate on the surface; and   analyzing the biofluid collected from the surface.   
     
     
         20 . The method of  claim 19 , wherein the device is configured to capture, collect, or store the biofluid.