According to an aspect, there is provided a system (10) comprising a sweat stimulation device (100) for stimulating sweat generation from sweat glands of a subject, the device comprising: a stimulation element (102) configured to provide modulated stimulation between two non-zero states to the sweat glands through the skin of the subject; and a sensor (104) for measuring data indicative of a characteristic of sweat generated by the sweat glands in response to the stimulation; and a processor (110) configured to receive the measured data from the sensor; compare the measured data with a threshold value; and responsive to determining that the measured data meets or exceeds the threshold value, generate an alert signal.

Methods and devices are provided for sweat inducement, which is useful in diagnostics, such as diagnosis of cystic fibrosis in a patient. The method includes applying a microneedle patch, which comprises microneedles which comprise pilocarpine or another sweat-inducing agent, to the skin of the patient effective to cause the microneedles to penetrate across the epidermis and into the dermis releasing the pilocarpine or another sweat-inducing agent into the skin in an amount effective to induce secretion of sweat from the skin. The secreted sweat can be collected and analyzed, for example by measuring chloride concentration in the sweat, which may be indicative of cystic fibrosis.

A system for thermoregulatory sweat testing of a subject includes a chamber for accommodating the subject, the chamber having a heating device for operably elevating the core body temperature of the subject to a target temperature so as to induce sweating over a skin surface of the subject; a cooling device for operably creating forced evaporative cooling of the skin surface of the subject after the core body temperature of the subject is elevated to the target temperature; an imaging device for acquiring images of the subject at different times, each image having imaged pixels, the imaging device including one or more infrared cameras, one or more infrared sensors, or a combination of them; and a controller coupled with the chamber and the imaging device for controlling operations of the chamber and the imaging device and processing the acquired images to determine skin surface sweat distributions of the subject.

A sweat sensing device includes at least one sweat generation unit capable of initiating sudomotor axon reflex (SAR) sweating in an indirect stimulation region and at least one analysis unit capable of sensing a physiological parameter of sweat, collecting a sweat sample, or a combination thereof. The at least one analysis unit is located above the indirect stimulation region when the sweat sensing device is placed on skin.

A wearable body composition analyzer according to various embodiments of the present disclosure may include an induction part for inducing secretion of bodily liquid while being in contact with a body part, a collection part that collects the bodily liquid secreted, a sensor part that detects a body composition from the bodily liquid collected, and a wearable part to which the induction part and the collection part is detachably attached, wherein the wearable part may be worn on a body. The above-described wearable body composition analyzer may be implemented variously according to embodiments.

A device (100) for sensing sweat on skin (12) includes a first analyte-specific sensor (120, 122) for sensing a first analyte in sweat; a sweat stimulating component (140); a waste collector (142, 144, 146, 148) beneath the sweat stimulating component (140); and an additional component being one or more of a sweat collector (130, 132, 134) or an additional analyte-specific sensor (124) for sensing an additional analyte in sweat that is different from the first analyte, the additional component being adjacent to and fluidically isolated from the waste collector (142, 144, 146, 148). A device (200) for sensing sweat on skin (12) includes a first portion comprising a first analyte-specific sensor (220) for sensing a first analyte in stimulated sweat and a sweat stimulating component (240); and a second portion comprising a second analyte-specific sensor (225, 226) for sensing a second analyte in natural sweat.

A wearable body composition analyzer according to various embodiments of the present disclosure may include an induction part for inducing secretion of bodily liquid while being in contact with a body part, a collection part that collects the bodily liquid secreted, a sensor part that detects a body composition from the bodily liquid collected, and a wearable part to which the induction part and the collection part is detachably attached, wherein the wearable part may be worn on a body. The above-described wearable body composition analyzer may be implemented variously according to embodiments.

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.

A sweat sensing device includes a plurality of sweat collection pads communicating with a sensor. Each of the pads is activated by a timing circuit which allows one or more of the pads to be activated at a selected time and subsequent deactivated after a defined period of time. This allows for selective collection of sweat from a plurality of pads over a prolonged period of time. An impedance measuring circuit can be employed to determine if one or more of the pads becomes disconnected, in order to avoid irritation. Further, the devices can use a common microfluidic device which both transports sweat activating substance, such as pilocarpine, to the surface of the skin and directs sweat away from the skin to a sensing device.

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.