Soft, skin-interfaced microfluidic systems with integrated immunoassays, fluorometric sensors, and impedance measurement capabilities

Abstract

Soft microfluidic systems that capture, store, and perform biomarker analysis of microliter volumes of sweat, in situ, as it emerges from the surface of the skin, represent an emerging class of wearable technology with powerful capabilities that complement those of traditional biophysical sensing devices. Recent work establishes applications in the real-time characterization of sweat dynamics and sweat chemistry in the context of sports performance and healthcare diagnostics. This paper presents a collection of advances in biochemical sensors and microfluidic designs that support multimodal operation in the monitoring of physiological signatures directly correlated to physical and mental stresses. These wireless, battery-free, skin-interfaced devices combine lateral flow immunoassays for cortisol, fluorometric assays for glucose and ascorbic acid (vitamin C), and digital tracking of skin galvanic responses. Systematic benchtop evaluations and field studies on human subjects highlight the key features of this platform for the continuous, noninvasive monitoring of biochemical and biophysical correlates of the stress state.

Battery-free, wireless soft sensors for continuous multi-site measurements of pressure and temperature from patients at risk for pressure injuries

“…One of the most promising strategies in this context leverages skin-like wireless device technologies that can noninvasively interface onto relevant regions of the anatomy for continuous monitoring of physiological signals relevant to various patient conditions [38][39][40][41][42][43][44] . A specific example involves sensors for pressure and temperature at a variety of skin interfaces, including those to mattresses 40 , prosthetic sockets 42 or skin-therapeutic compression garments 41 .…”

TiO2 Nanotubes Alginate Hydrogel Scaffold for Rapid Sensing of Sweat Biomarkers: Lactate and Glucose

“…Moreover, it shows a bright future to be used in wearable microfluidic devices for sweat monitoring due to its ease of integration and biocompatibility. 18 , 64 …”

Decoding of the coupling between brain and skin activities in olfactory stimulation by analysis of EEG and GSR signals

“…Therefore, we conclude that the changes in the activity of the skin are correlated with the changes in the activity of the brain. This investigation is novel in comparison to the published studies [1][2][3][4][5][6][7][8] that investigated the reaction of skin under different conditions without attempting to link it to brain activity.…”

“…In most of the reported works, Galvanic Skin Response (GSR) signals are considered as the index of skin activity. The reported studies that evaluated GSR signals to analyze emotions [1,2] and stress [3,4], to identify driver distraction [5], to investigate the effectiveness of social advertising [6], to analyze the sleep quality of older adults [7], and to detect pain [8] are worthy of being mentioned.…”