The invention provides a variety of novel devices, systems, and methods of utilizing mixed-ionic-electronic conductor (MIEC) materials adapted to function with an applied current or potential. The materials, as part of a circuit, are placed in contact with a part of a human or nonhuman animal body. A sodium selective membrane system utilizing the MIEC is also described.

An apparatus for analyzing an in vivo component is provided. The apparatus for analyzing an in vivo component may include an impedance sensor including a first electrode and a second electrode configured to contact a fluid channel of a fluid to be analyzed. The apparatus may include an impedance measurement device configured to apply a current to the first electrode and the second electrode, measure a voltage between the first electrode and the second electrode based on applying the current, and measure an impedance of the fluid based on the measured voltage. The apparatus may include a processor configured to model the measured impedance using an equivalent circuit; and analyze the in vivo component based on modeling the measured impedance using the equivalent circuit.

An apparatus for analyzing an in vivo component is provided. The apparatus for analyzing an in vivo component may include an impedance sensor including a first electrode and a second electrode configured to contact a fluid channel of a fluid to be analyzed. The apparatus may include an impedance measurement device configured to apply a current to the first electrode and the second electrode, measure a voltage between the first electrode and the second electrode based on applying the current, and measure an impedance of the fluid based on the measured voltage. The apparatus may include a processor configured to model the measured impedance using an equivalent circuit; and analyze the in vivo component based on modeling the measured impedance using the equivalent circuit.

A apparatus for estimating concentration may include: a spectrum obtainer configured to obtain Raman spectra of an object; and a processor configured to extract, from the Raman spectra, at least one analyte spectrum related to an analyte and at least one non-analyte spectrum related to a biological component other than the analyte, and estimate concentration of the analyte based on a first area under a curve of the at least one analyte spectrum and a second area under a curve of the at least one non-analyte spectrum.

A apparatus for estimating concentration may include: a spectrum obtainer configured to obtain Raman spectra of an object; and a processor configured to extract, from the Raman spectra, at least one analyte spectrum related to an analyte and at least one non-analyte spectrum related to a biological component other than the analyte, and estimate concentration of the analyte based on a first area under a curve of the at least one analyte spectrum and a second area under a curve of the at least one non-analyte spectrum.

Activity monitoring systems and methods are disclosed. Systems include a continuous glucose monitoring device for a user including a glucose sensor for monitoring blood glucose levels of the user during an activity. An activity monitoring device is associated with the user and includes an activity sensor for tracking movement of the user during the activity. A display device is associable with the user during the activity. At least one processor is configured to execute program instructions configurable to cause the at least one processor to: receive activity data from the activity monitoring device; cause to be displayed at least some of the activity data on the display device; receive blood glucose data from the continuous glucose monitoring device; determine a product consumption recommendation based on the blood glucose data and the activity data, wherein the product consumption recommendation includes a recommendation of when the user should consume carbohydrates in order to maintain blood glucose levels within a specified target range during the activity; cause to be displayed the product consumption recommendation on the display device; and record an activity log including the activity data and the blood glucose data with respect to time.

Activity monitoring systems and methods are disclosed. Systems include a continuous glucose monitoring device for a user including a glucose sensor for monitoring blood glucose levels of the user during an activity. An activity monitoring device is associated with the user and includes an activity sensor for tracking movement of the user during the activity. A display device is associable with the user during the activity. At least one processor is configured to execute program instructions configurable to cause the at least one processor to: receive activity data from the activity monitoring device; cause to be displayed at least some of the activity data on the display device; receive blood glucose data from the continuous glucose monitoring device; determine a product consumption recommendation based on the blood glucose data and the activity data, wherein the product consumption recommendation includes a recommendation of when the user should consume carbohydrates in order to maintain blood glucose levels within a specified target range during the activity; cause to be displayed the product consumption recommendation on the display device; and record an activity log including the activity data and the blood glucose data with respect to time.

In certain embodiments a microfluidic patch is provided that allows continuous analysis of natural sweat at various body locations of sedentary individuals. In certain embodiments the patch provides integrated electrical sweat rate sensor and electrochemical sensors to enable simultaneous detection of sweat rate and compositions such as pH, Cl.sup.−, and levodopa. The patch can facilitate dynamic sweat analysis related to light physical activities, hypoglycemia-induced sweating, and levodopa sensing for Parkinson's disease management. The device enables routine analysis of natural sweat dynamics arising from different physical and physiological functions which cannot be realized by current wearable sweat sensors.

In certain embodiments a microfluidic patch is provided that allows continuous analysis of natural sweat at various body locations of sedentary individuals. In certain embodiments the patch provides integrated electrical sweat rate sensor and electrochemical sensors to enable simultaneous detection of sweat rate and compositions such as pH, Cl.sup.−, and levodopa. The patch can facilitate dynamic sweat analysis related to light physical activities, hypoglycemia-induced sweating, and levodopa sensing for Parkinson's disease management. The device enables routine analysis of natural sweat dynamics arising from different physical and physiological functions which cannot be realized by current wearable sweat sensors.

A method includes monitoring, via a device including an electrochemical cell, an electrical current that is proportional to an impedance of the electrochemical cell, and responsive to determining that the electrical current satisfies a threshold, measuring, via the device, a plurality of impedances of the electrochemical cell corresponding to a plurality of frequencies. The method further includes determining a charge transfer conductance and a solution resistance based on the plurality of impedances at fewer than four of the corresponding plurality of frequencies and determining the presence of electrochemical interference based on the solution resistance and the charge transfer conductance. The method further includes outputting an alert based on the determination of the presence of electrochemical interference.