Requirements Specification

A requirements specification for applicable scenarios is defined in cooperation with the application partners. The aim is to develop systems that are suitable for the separate and combined detection of elements in exhaled breath and sweat. The systems should be designed in such a way that sensor setup and positioning are adapted to operational conditions and detection methods. For example, basic modules are to be developed for mobile respiratory gas analysis and mobile sweat monitoring. These modules can be continuously enhanced by the integration of further sensor components. In this planned project, new sensor components will be integrated into these basic modules for respiratory gas and sweat monitoring. These new sensor components are based on nanolayer sensors. In VITAL-SENSE, they are used to detect elements that are described in the literature as indicators of stress, exhaustion, dehydration, disease, and acute conditions. The specific role of users is relevant to the definition of the requirements specification, particularly when it comes to the system design. For example, the position of the sensors on the subject is crucial for reliable and usable results. The system should enable permanent personalized monitoring. This makes it easier to assign the measured concentration of the target elements to a normal, healthy condition of the subject, a (chronic) disease, an acute condition, stress, exhaustion, or dehydration.

Sensor Components

Vital Parameters in Respiratory Gas

Acetone and isoprene can be found in respiratory gas and are suitable indicators of stress and exhaustion. Ammonia and aldehydes, such as hexanal and pentanal, can be indications of a kidney dysfunction. Abnormal humidity in respiratory gases can indicate renal failure, diabetes mellitus or acute loss of water. The combination of information from respiratory gas measurements and ion detection in sweat is relevant for interpreting results. The development of nanolayer-based sensors in the VITAL-SENSE project focuses on the detection of acetone, isoprene, ammonia, and hexanal.

Vital Parameters in Sweat

The current literature describes cortisol, which is detectable in sweat, as one of the most important early indicators of stress. Another relevant parameter in sweat is sodium ion concentration. This can point to dehydration, a kidney dysfunction, or diabetes mellitus, provided that information is available on possible loss of water. In the VITAL-SENSE project, systems are being designed for the detection of organic compounds and ions in sweat. For example, cortisol and sodium ion concentration are detected.