A moisture sensor includes a pair of electrode plates separated by a moisture absorbent material that forms the dielectric of a capacitive sensor. As the absorbent dielectric material absorbs moisture, such as perspiration, the capacitance of the sensor changes reflecting a quantitative measure of perspiration absorbed. The sensor can be stabilized by capacitively coupling the dielectric material to the skin of the user to improve sensor stability and noise rejection. The sensor can include a capacitive sensing integrated circuit that measures the capacitance of the sensor in close proximity to the electrodes to limit the introduction of noise.

Systems and methods for processing sensor data and self-calibration are provided. In some embodiments, systems and methods are provided which are capable of calibrating a continuous analyte sensor based on an initial sensitivity, and then continuously performing self-calibration without using, or with reduced use of, reference measurements. In certain embodiments, a sensitivity of the analyte sensor is determined by applying an estimative algorithm that is a function of certain parameters. Also described herein are systems and methods for determining a property of an analyte sensor using a stimulus signal. The sensor property can be used to compensate sensor data for sensitivity drift, or determine another property associated with the sensor, such as temperature, sensor membrane damage, moisture ingress in sensor electronics, and scaling factors.

Systems and methods for processing sensor data and self-calibration are provided. In some embodiments, systems and methods are provided which are capable of calibrating a continuous analyte sensor based on an initial sensitivity, and then continuously performing self-calibration without using, or with reduced use of, reference measurements. In certain embodiments, a sensitivity of the analyte sensor is determined by applying an estimative algorithm that is a function of certain parameters. Also described herein are systems and methods for determining a property of an analyte sensor using a stimulus signal. The sensor property can be used to compensate sensor data for sensitivity drift, or determine another property associated with the sensor, such as temperature, sensor membrane damage, moisture ingress in sensor electronics, and scaling factors.

Embodiments describing an approach for detecting user biomarker identifier changes based on audio preferences and generating biometric alerts based on the detected biomarker identifier changes. Receiving a user's current audio preferences. Retrieving the user's historic audio preferences and biometric data associated with the user's historic audio preferences. Analyzing the user's current audio preferences based on the user's historic audio preferences and the biometric data associated with the historic audio preferences. Creating a user biometric profile based on analyzing the user's current audio preferences, the user's historic audio preferences and the biometric data associated with the user's historic audio preferences; and outputting the user biometric profile.

The disclosed invention provides a biofluid sensing device configured with a membrane-enhanced sensor located in a sweat collector. The disclosed analyte-specific sensor is configured to reduce required biofluid sample volume due to its close proximity to the skin and source of sweat biofluid. The sensor is contained within a pH and salinity-stabilized fluid that, in turn, is contained in a selectively permeable membrane to improve sensor performance in variable biofluids, and to protect the sensor from skin contact. In one embodiment, the biofluid sensing device includes means to protect the self-aligning sensors from abrasion against the skin or device components. Other embodiments of the disclosed invention include a track-etched membrane to provide sensor protection.

Embodiments of the disclosed invention provide devices for measuring concentrations of bound and unbound fractions of a target analyte in a biofluid sample. Analytes present in biofluid may be found in a free state, or bound to a binding solute, presenting difficulties for wearable analyte sensors to measure physiologically significant concentrations of the analyte in biofluid. The disclosed devices feature sensors configured to measure both the bound and unbound fractions of the analyte, as well as analyte releasers that cause a portion of the bound fraction of analytes to be released to facilitate measurement. Some embodiments include a collector and or a sample conduit. Other embodiments include a plurality of fluid pathways.

A perspiration sensing system includes a sensor patch and a smart device. The sensor patch includes one or more perspiration sensing portions. The one or more perspiration sensing portions include an inlet having a predefined size to receive perspiration from a predefined number of sweat glands and an outlet for reducing back pressure. At least one perspiration sensing portion includes a channel having a colorimetric sensing material that changes color when exposed to perspiration. At least one perspiration sensing portion includes a colorimetric assay in a substrate that changes color when exposed to biochemical components of perspiration. The system further includes a smart device having a camera that can take a picture of the sensor patch and determine the volume, rate of perspiration, and/or biochemical components of the perspiration from the one or more perspiration sensing portions.

Example embodiments relate to a system for monitoring biosignals and also to a patch and an apparatus which may include part of the system. The system may include a patch including a surface for attachment to a user, first sensors for sensing respective first biosignals of the user, and a transmitter for wirelessly transmitting first biosignal data representing the first biosignals of the user. The system may also include an apparatus for being worn or placed over the patch, the apparatus including second sensors at or near a lower surface thereof for sensing respective second biosignals of the user and providing second biosignal data representing the second biosignals. The apparatus may also include a receiver for wirelessly receiving the first biosignal data from the patch. The patch may include recesses or apertures for alignment with the second sensors when the apparatus is worn or placed over the patch.

A wearable consumer electronic product includes at least a housing arranged to carry operational components comprising a processor and a band having a pliable band body and a securing means arranged to secure the band body to the housing. In one embodiment, the pliable band body has a size and shape suitable for wrapping around an individual appendage and that includes an opening that leads to a cavity within the band body suitable for accumulating an amount of water and a band sensor embedded within the band body in communication with the cavity.

Described here are patches and methods for measuring glucose in sweat (and tears and the like). In general, the patches comprise an adhesive layer adapted to bond to skin of an individual, a substrate layer disposed over the adhesive layer and comprising a glucose sensing complex including a chromogen that changes color in the presence of certain concentrations of glucose, and a cover. In typical embodiments, the substrate layer has elements formed to direct and accumulate sweat that migrates from the skin of the individual to the glucose sensing complex. Methods of using the invention can comprise cleaning the skin surface, collecting sweat in a patch comprising this microfluidic constellation of elements, and observing concentrations of glucose collected in the sweat, for example either visually, or by using a smartphone or other computer processing device.