Wearable Circuits Sintered at Room Temperature Directly on the Skin Surface for Health Monitoring

Abstract

A soft body area sensor network presents a promising direction in wearable devices to integrate on-body sensors for physiological signal monitoring and flexible printed circuit boards (FPCBs) for signal conditioning/readout and wireless transmission. However, its realization currently relies on various sophisticated fabrication approaches such as lithography or direct printing on a carrier substrate before attaching to the body. Here, we report a universal fabrication scheme to enable printing and room-temperature sintering of the metal nanoparticle on paper/fabric for FPCBs and directly on the human skin for onbody sensors with a novel sintering aid layer. Consisting of polyvinyl alcohol (PVA) paste and nanoadditives in the water, the sintering aid layer reduces the sintering temperature. Together with the significantly decreased surface roughness, it allows for the integration of a submicron-thick conductive pattern with enhanced electromechanical performance. Various on-body sensors integrated with an FPCB to detect health conditions illustrate a system-level example.

Textile Triboelectric Nanogenerators for Wearable Pulse Wave Monitoring

“…Taking advantage of the textile industry, commercial looms can manufacture textile TENGs at scale with 2D and even 3D geometries [98]. Meanwhile, printed electronic technologies can fabricate large-scale circuits, such as filter, amplifier, and antenna circuits, on textiles, clothes, and even human skin [99]. These scalable strategies are expected to promote the future extensive use of textile TENGs.…”

Micro/nanodevices for assessment and treatment in stomatology and ophthalmology

“…Microneedles and other micro/ nanodevices may be applied for the delivery of macromolecular drugs, DNA, and genes for the treatment of genetic diseases. Drug delivery and treatment devices can also be combined with sensing components, especially in stretchable and wearable forms [106][107][108][109] , to provide feedback loop control for more effective treatment. Nevertheless, joint efforts from both clinicians and engineers with diverse backgrounds are highly desirable to explore these vast opportunities, and help address the major challenges in this burgeoning field.…”

Design of Flexible Pressure Sensor Based on Conical Microstructure PDMS-Bilayer Graphene

“…With the development of materials science, sensors with flexible substrates have gradually attracted people’s attention, especially the enthusiasm for research on electronic skin is increasing. Due to the flexibility, high sensitivity, high fit, and comfort of electronic skin [ 1 , 2 , 3 , 4 ], it can sense different external pressure like human skin as a biomedical sensor, that is, it has smooth conductive tactile signals. Flexible sensors can be applied not only to the medical field, but also to wearable devices and intelligent robot systems [ 5 , 6 , 7 ].…”