Development of a data acquisition system for quantifying electrolytes in sweat
DOI:
https://doi.org/10.37636/recit.v9n3e484Keywords:
Dehydration, Embedded system, Ions, Non-invasive monitoring, Signal conditioningAbstract
Monitoring hydration status is important in clinical settings, particularly in vulnerable patients, such as the elderly and newborns, where conventional methods, such as blood tests, are invasive and impractical for continuous assessment. In this study, a non-invasive, portable system was developed to assess hydration status by detecting sodium (Na⁺), ions present in sweat. Low-cost potentiometric sensors were used, employing electrodes with a carbon-based sensing interface. These sensors were integrated into an embedded system for data acquisition that included signal conditioning and amplification stages, implemented at the circuit level using an AD620. The data acquisition was carried out via USB transmission from an Arduino Nano to an interface developed in Python, which enabled the processing, analysis, and visualization of data related to potentiometric measurements. The system was validated by comparing potential measurements for Na⁺ concentrations ranging from 10 to 200 mM with those obtained using a commercial device, yielding an MSE of 129.56, an RMSE of 11.38, an MAE of 7.9, and an R2 of 0.93. Unlike previous studies that use expensive materials or communication dependent on Wi-Fi infrastructure, the developed system prioritized non-invasiveness and portability, enabling the analysis of voltage signals associated with ion concentration in sweat.
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![A) System with silver electrodes. B) Flexible, wireless device with sweat sensors. Adapted from [17] and [11].](https://recit.uabc.mx/public/journals/1/submission_484_484_coverImage_en.png)
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Data Availability Statement
The data supporting the findings of this study are available from the corresponding author upon reasonable request.
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Copyright (c) 2026 Carolina Michelle Santillán Cruz, Reyna del Carmen Gutiérrez Gutiérrez, Moisés Israel Salazar Gastélum, José Ricardo Cárdenas Valdez, Mara Beltrán Gastélum
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