Abstract: The present invention provides a biofluid sensing device capable of concentrating a biofluid sample with respect to a target analyte, so that the analyte can be accurately detected or measured by EAB sensors. Methods for using such a device provide qualitative information about the presence of the analyte, and/or quantitative information about relative concentrations of the analyte in the biofluid. The disclosed device includes a concentration channel for concentrating the biofluid sample, as well as a selectively permeable membrane, one or more EAB sensors, and one or more secondary sensors carried on a water-impermeable substrate. A method for using the disclosed device to collect a biofluid sample, concentrate the sample relative to a target analyte, and measure the target analyte is also disclosed.

Abstract: Electrochemical aptamer-based biosensing devices and methods are described herein that are configured to produce a detectible signal upon target analyte interaction, with reduced reliance on a conformational change by the aptamer. The disclosure includes embodiments of docked aptamer EAB sensors for measuring the presence of a target analyte in a biofluid sample. The sensors include an electrode capable of sensing redox events, and a plurality of aptamer sensing elements with aptamers selected to interact with a target analyte. Each aptamer sensing element includes a molecular docking structure attached to the electrode, and an analyte capture complex that includes an aptamer releasably bound to the docking structure, and an electroactive redox moiety. Upon the aptamer binding with a target analyte, the analyte capture complex separates from the docking structure.

Abstract: Embodiments of the disclosed invention provide devices and methods to incorporate suspension-based, i.e., hydrogel-based and thixotropic compound-based, ion-selective electrodes and reference electrodes into a wearable sweat sensing device. Embodiments of this device are configured to monitor sweat electrolyte concentrations, trends, and ratios under demanding use conditions. The accompanying method includes use of the disclosed device to track fluid and electrolyte gain and loss in order to produce an electrolyte estimate, such as a sweat electrolyte concentration, a sweat electrolyte concentration trend, a sweat rate, or a concentration ratio between a plurality of electrolytes.

Abstract: The present invention provides a biofluid sensing device capable of concentrating a biofluid sample with respect to a target analyte, so that the analyte can be accurately detected or measured by EAB sensors. Methods for using such a device provide qualitative information about the presence of the analyte, and/or quantitative information about relative concentrations of the analyte in the biofluid. The disclosed device includes a concentration channel for concentrating the biofluid sample, as well as a selectively permeable membrane, one or more EAB sensors, and one or more secondary sensors carried on a water-impermeable substrate. A method for using the disclosed device to collect a biofluid sample, concentrate the sample relative to a target analyte, and measure the target analyte is also disclosed.

Abstract: The disclosed invention includes integrative electrochemical aptamer-based sensors for use in wearable biofluid sensing devices. The disclosed integrative EAB sensors are configured to detect very low concentrations of target analytes in a sweat or biofluid sample by aggregating signals from individual sensing elements over time until a signal threshold is reached. Signal aggregation is accomplished through various retention structures that extend the time sensing elements retain target analyte molecules. Embodiments include attaching complementary primers and functional groups to the aptamer, covering such retention structures with blockers until analyte capture, or coating the sensor electrode with a hydrophilic and hydrophobic monolayer. The invention also includes methods of using the disclosed integrative sensors. Some embodiments of the disclosed method include tracking time to signal threshold to estimate analyte concentration.

Abstract: The disclosed invention includes methods to employ wearable biosensing devices to accomplish the following: 1) screen for the presence of a disease or infection, including pre-symptomatic detection, and determination of the type (e.g., viral, bacterial, or fungal) of disease or infection present; 2) confirm the antigen and monitor the progress of an active infection; and 3) monitor the efficacy of a treatment program for a disease or infection. Such methods rely on the detection, in sweat or other biofluids, of proteins, nucleotides, DNA polymerases, proteases, group-specific antigens, antibodies, cytokines, or other molecules, that are produced by the body as part of the innate or adaptive immune responses to an infectious agent, or the infectious agent itself, its products, or derivatives. Some embodiments comprise a method of using such a biosensing device as a biosentinel against biological threats.

Abstract: The disclosed invention addresses an unmet need of biofluid analysis by utilizing the presence of certain nucleotides, e.g., microDNA, eccDNA, DNA fragments, microRNA, RNA fragments, and peptides, in a sample biofluid, such as eccrine sweat, apocrine sweat, blood, serum, saliva or tears, to perform a number of physiological sensing functions. Specifically, the present disclosure provides: (1) a device and method of determining whether a biofluid sensing device is being worn by a specific individual based on a measurement of nucleotides in a biofluid; (2) a device and method of recognizing at least one physiological disease or condition based on nucleotide concentrations, ratios, or trends in a biofluid.

Abstract: Embodiments of the disclosed invention provide devices and methods to incorporate suspension-based, i.e., hydrogel-based and thixotropic compound-based, ion-selective electrodes and reference electrodes into a wearable sweat sensing device. Embodiments of this device are configured to monitor sweat electrolyte concentrations, trends, and ratios under demanding use conditions. The accompanying method includes use of the disclosed device to track fluid and electrolyte gain and loss in order to produce an electrolyte estimate, such as a sweat electrolyte concentration, a sweat electrolyte concentration trend, a sweat rate, or a concentration ratio between a plurality of electrolytes.

Abstract: The disclosed invention incorporates sweat sensing devices into headgear so that accurate biofluid analyte measurements may be made during physical activity. As disclosed herein, a sweat sensing device may be incorporated into an inner surface or support structure of headgear, including hardhats, sports headgear, flight helmets, combat helmets, sweatbands, sports caps, visors, and masks. The device is further configured to recognize and alter operational states when the device is not in adequate skin contact for operation. Some embodiments are fully disposable, and other embodiments include a reusable component that may be integrated into, or attached to, the headgear.

Abstract: The disclosure provides: a two-way communication means between a sweat sensing device and a user; at least one means of activating, deactivating, controlling the sampling rate, and controlling the electrical power applied to a particular sweat sensor or group of sensors; a means of isolating a sweat sensor from sweat until needed; a means of selectively stimulating sweat for a particular sweat sensor or group of sensors to manage sweat flow or generation rate; a means of monitoring the power consumption of a sensor device, individual sensors or groups of sensors; a means of monitoring an individual sweat sensor or group of sensors for optimal performance; a means of monitoring whether a sweat sensing patch is in adequate proximity to a wearer's skin to allow device operation; and the ability to use aggregated sweat sensor data correlated with external information to enhance the device's management capabilities.

Abstract: Methods and systems are disclosed for defining physiological states using sweat-sensing devices. An output of sweat-sensing devices is defined by identifying a set of sweat sensor values. Each sweat sensor value of the set of sweat sensor values includes an electrical-signal value produced by a sensor. For each sweat sensor value of the set of sweat sensor values, the electrical-signal value of the sweat sensor value is translated into a voltage value thereby generating a translated sweat sensor value. Each translated sweat sensor value is calibrated by transforming, upon applying a hardware correction value to the translated sweat sensor value, the voltage value into a physiological value. The calibrated sweat sensor values are aggregated and the calibrated seat sensors values are then modified using received environmental inputs. An output is then generated based on the modified sweat sensor values.

Abstract: The disclosed invention includes: a device and method of performing physiological sweat sensing device calibration; a device and method of indicating an individual's dehydration state; a device and method of indicating an individual's stage in their ovulation cycle; a device and method of indicating that an individual is hypokalemic or hyperkalemic; a device and method of indicating that an individual is entering a hypoglycemic state; a device and method of indicating an individual's glucose trend value; and a device and method of indicating that an individual has experienced toxic substance exposure.

Abstract: The present disclosure includes a device and method of measuring an individual's cortisol awakening response; a device and method of measuring an individual's diurnal cortisone level, including the basal cortisol level; a device and method of indicating an individual's stress profile based on sweat cortisol measurements; a device for measuring and interpreting sweat analytes relevant to risk-taking behavior; and a method of determining an individual's risk-taking propensity based on measurement and development of sweat analyte profiles.

Abstract: A wearable sweat sensing device is provided for managing excess sweat flow. The sweat sensing device includes at least one sweat sensor and a sweat path for conveying sweat from a wearer's skin and across the at least one sensor. At least one adaptive sweat flow component is in fluidic communication with the sweat path for removing excess sweat flow from the sweat path. The adaptive sweat flow component can include one or more of an adaptive sweat sample collector, an adaptive sweat sample channel, or an adaptive sweat sample pump. A method of using the disclosed device to remove excess sweat flow from the device's sweat path during periods of high sweat rate is also provided.

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.