Simultaneous multi-location wireless monitoring of sweat lactate trends

Abstract

Wearable device technologies for sweat analytics present a versatile application for monitoring physiological state, which can circumvent the requirement for inconvenient and invasive blood sampling. This paper reports a miniature electrochemical sensor platform for non-invasive and wireless real-time monitoring of lactate in exercise-induced human sweat. The conformal and low profile sensor platform is composed of (a) a flexible electronic readout tag with wireless charging and data acquisition, and (b) a disposable enzymatic amperometric biosensor patch with electrodes fabricated using high throughput roll-to-roll processing. Data were generated in real time from sensor response to lactate in exercise-induced sweat from multiple body regions simultaneously. The biosensor demonstrates current response proportional to lactate at physiological concentration range between 5 and 30 mM. This developed platform can be adapted for sensing of other sweat constituents including ions or metabolites, and therefore advances wearable technology for personalized physiological monitoring

State of Sweat: Emerging Wearable Systems for Real-Time, Noninvasive Sweat Sensing and Analytics

“…Other wearable sensor designs seek to harness blood-correlated biomarkers beyond chloride and glucose (e.g., lactate, − ethanol, and cortisol , ) to address diagnostic challenges related to diabetes and other diseases. Recent examples of wearable electrochemical sensing platforms demonstrate the promise of sweat analytics for monitoring biomolecular changes relevant to diseases such as gout (uric acid, Figure F) or general conditions such as fever (cytokines, Figure G).…”

Wearable Electrodes for Lactate: Applications in Enzyme‐Based Sensors and Energy Biodevices

“…Typically, the aim is to generate a bioelectronic signal whose magnitude, [5] frequency, [6] or other measurable signals are proportional to the concentration of a specific analyte or a group of analytes to which the biosensing element binds. [7][8] In this review, bioelectronic signals are referred to as electrochemical signals, such as current, [9][10] voltage, [11] and impedance. [12] Over the past decades, the trend of biosensors has been transitioning from traditional biosensing technologies to modern wearable devices that can be used by non-expert individuals.…”

Recent Advances in Wearable Biosensors for Non-Invasive Detection of Human Lactate

“…Enzymes (lactate dehydrogenase (LDH) and lactate oxidase (LOx/LOD)) are frequently added to make the sensor selective. Prussian blue (PB), which is a good electron transfer mediator and can lower the redox reaction potential, can also be employed to further limit the introduction of interfering signals and improve sensor selectivity [ 38 , 39 , 40 , 41 , 42 , 43 ]. Additionally, a layer of semi-permeable membrane, made by perfluorosulfonic acid type polymers (Nafion) with specific size or charge molecule repulsion can also be coated on the electrode surface to lessen the passage of interfering species [ 9 , 44 ].…”