Abstract: Described are sensing devices and methods for detecting at least one analyte in a sample solution. The sensor is capable of a pre-storage state, a storage state and a sensing state. The sensor includes at least one substrate-adjacent aptamer; where the sensor, in the absence of a material to reduce or prevent degradation, would incur significant degradation when the sensor is placed in a storage state. The sensor further includes at least one material which reduces or prevents the significant degradation during the storage state.

Abstract: A device and method for detecting the presence of, or measuring the concentration or amount of, at least one analyte in a sample fluid. The device 100 includes at least one electrode 150, a sensor fluid 18, a plurality of aptamers freely diffusing in the sensor fluid, and a plurality of redox tags associated with at least a subset of aptamers of the plurality of aptamers. The sensor fluid is capable of having a sample fluid 14 introduced thereinto, and the detection or measurement of any analyte may occur through a change in electron transfer from at least one redox tag of the plurality of redox tags.

Abstract: A device and method for continuously sensing at least one target analyte in a sample fluid. The device 100 includes a plurality of electrochemical aptamer sensors 120, 122, 124, 126; and at least one gating component 132, 134, 136 associated with at least one electrochemical aptamer sensor of the plurality of electrochemical aptamer sensors. The method includes bringing a sample fluid 190 into contact with the device, and determining or measuring a change in an electrical current associated with the at least one electrochemical aptamer sensor to (1) determine the presence of an analyte in the sample fluid, or (2) measure the amount or concentration of an analyte in the sample fluid.

Abstract: Devices and methods for measuring an analyte. A sensing device includes a sensor and a detection circuit operatively coupled to the sensor. The sensor includes a working electrode having an aptamer and an attached redox couple to electrochemically measure the analyte. The detection circuit is configured to apply a first scan having a first scan range to the sensor, and determine a position of a redox peak in the first scan. In response to the first scan range not matching the position of the redox peak, the detector circuit defines a second scan range that matches the position of the redox peak, and applies a second scan having the second scan range to the sensor.

Abstract: A device and method for detecting the presence of, or measuring the concentration of amount of, at least one analyte in a sample fluid. The device includes a sensor fluid (18), a plurality of adapter molecules (980) in the sensor fluid that are capable of binding to an analyte, a plurality of aptamers (970) in the sensor fluid that are capable of binding to the analyte when analyte is bound to one or more adapter molecules of the plurality of adapter molecules, at least one membrane (936) in communication with the sensor fluid, and at least one detection component that is capable of detecting the binding of analyte by one or more of the plurality of aptamers. The membrane is permeable to the analyte but impermeable to the adapter molecule.

Abstract: A device for measuring the concentration of a target analyte in a sample fluid. The device (100) includes a housing (110) defining a plurality of chambers including at least a first chamber (112) and a second chamber (114). The first chamber includes a sensor fluid (132) therein, and the second chamber includes a reservoir fluid (134) therein. A sample fluid area (116) is also defined by the housing. This sample fluid area is capable of receiving a sample fluid (130) to be tested for the presence or concentration of a target analyte. A first element (140) separates the first chamber from the sample fluid area and restricts diffusion of solutes between the sensor fluid and sample fluid. A second element (142) separates the first chamber from the second chamber and restricts diffusion of solutes between the sensor fluid and the reservoir fluid. The device also includes at least one sensing electrode (120) that is positioned in the sensor fluid.

Abstract: Devices and methods for measuring an analyte. A sensing device 156 includes a sensor and a detection circuit operatively coupled to the sensor. The sensor includes a working electrode having an aptamer and an attached redox couple to electrochemically measure the analyte. The detection circuit is configured to perform a partial scan of the sensor, wherein the partial scan includes only a portion of a full scan. The working electrode may be one of a plurality of working electrodes, and the detection circuit may perform the partial scan on a different subset of the plurality of working electrodes on each of a plurality of measurement cycles. Partial scans may include partial voltage scans, partial current scans, or partial frequency scans.

Abstract: A device and method for detecting the presence of, or measuring the amount or concentration of, at least one analyte in a sample fluid, where the device includes a dissolvable material, and a plurality of aptamers disposed in and/or on the dissolvable material, and where one or more aptamers of the plurality of aptamers (1) are capable of binding at least one analyte, and (2) have at least one redox tag attached thereto.

Abstract: A device and method including at least one electrochemical aptamer sensor for small sample volume sensing. The device (100) includes at least one substrate (110) that defines a microfluidic feature (118) having a defined volume. At least one electrochemical aptamer sensor (120), including an electrode (122) associated with a plurality of aptamers (124), is carried by the substrate and is in fluid communication with the defined volume. The defined volume is capable of containing less than 30 ?L of a sample fluid when the defined volume is filled with the sample fluid. Additionally, or alternatively, the volume of the sample fluid in ?L is equal to C * the surface area of the electrode in cm2 that is associated with the plurality of aptamers/concentration of the target analyte in ?M; and C has a value chosen from less than 4, less than 0.4, less than 0.04, and less than 0.004.

Abstract: Provided herein are devices and methods for monitoring biofluids related to ovulation. Such devices include the use of electrochemical aptamer-based (EAB) sensors.

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: Embodiments of the disclosed invention provide wearable devices that use a humidity sensor to measure sweat rate generated from an area of skin. A sensing chamber is continuously filled with a sweat sample, which forms a droplet and alters the humidity measured within the chamber. Once the sweat sample droplet expands to the edge of the chamber, the droplet contacts a wick and is drawn away, so the chamber can fill with a subsequent droplet. The device uses a droplet volume and the time required to reach a maximum humidity to calculate a sweat rate. A pump is used to draw old sweat sample out of the wick to allow extended device operation. Some embodiments also include capacitive sensors to perform back up measurements. Another set of embodiments includes alternatively shaped sensing chambers configured to reduce sample volumes or improve function. A method for determining sweat rate based on humidity sensor measurements is also included.

Abstract: Challenges of the sweat medium for electrochemical aptamer-based biosensor (“EAB sensor”) devices can be mitigated through aptamer selection, sensor/device configuration and physiological algorithms that account for the effects of (1) target analyte size, (2) potential concentration ranges, (3) sweat sample pH, and (4) sweat sample salinity. The disclosed invention includes a method of aptamer selection for use in an EAB sensor configured for use in a wearable sweat sensing device. The disclosed invention further provides a sweat sensing device configured to use EAB sensors to detect target analytes in a sweat sample.

Abstract: The disclosed invention provides a sweat sensing device configured with self-aligned sweat stimulation means to provide adequate sweat generation for continuous monitoring of sweat. The disclosed device includes one or more analyte-specific sweat sensors that self-align with sweat glands. In one embodiment, the sweat sensing device includes means to protect the self-aligning sensors from abrasion against the skin or device components. In another embodiment, the device includes prolonged sweat stimulation for the self-aligning sensors through diffusion of a sweat stimulating compound into the skin.

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 provides sweat sensing devices with smart sweat stimulation and sensing embodiments: which improve the dependability and predictability of sweat sampling rates; achieve a desired number of sweat sampling events per day while minimizing skin irritation and prolonging device lifespan; and use physical, optical or thermal sweat stimulation to augment or replace chemical sweat stimulation.

Abstract: The disclosed invention provides a sensing device capable of concentrating a fluid sample with respect to a target analyte and a reference analyte, and measuring the target analyte and reference analyte in the concentrated sample. The invention includes a concentrator that may include a selectively permeable membrane, or a gel having an increasing density gradient. In another embodiment, the invention includes an air or gas gap between a fluid transport channel and the concentrator. In another embodiment, the sensing device includes a driver for electronically moving a fluid sample through the channel and membrane to cause concentration. In some embodiments, the invention may also determine the change in molarity of the fluid sample with respect to the target analyte, as the sample is concentrated by the device.

Abstract: The disclosed invention provides a fluid sensing device and method capable of collecting a fluid sample, concentrating the sample with respect to one or more target analytes, and measuring the target analyte(s) in the concentrated sample. The invention is also capable of determining the change in molarity of the fluid sample with respect to the target analyte(s), as the sample is concentrated by the device. The invention further includes a method for using a fluid sensing device to concentrate a fluid sample with respect to one or more target analytes. The disclosed method further includes the ability to correlate the measured target analyte concentration to a physiological condition of a device wearer, or of a fluid source.

Abstract: The disclosed invention includes sweat sensing devices configured to periodically measure sweat conductivity and galvanic skin response, devices to measure volumetric sweat flow rate, and devices that combine the three functions. The disclosure further includes methods for using a device configured to perform periodic sweat conductivity measurements, galvanic skin response measurements, and volumetric sweat rate measurements so that each sensor modality informs composite estimates of sweat onset, sweat cessation, sweat ion concentration, and sweat rate. The method uses those measurements to inform other sweat sensing device functions, such as determining the existence of a physiological condition, or performing measurements of concentrations, ratios, and trends of sweat analytes.

Abstract: 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.