A wireless optoelectronic skin patch for light delivery and thermal monitoring

Abstract

Summary Wearable optoelectronic devices can interface with the skin for applications in continuous health monitoring and light-based therapy. Measurement of the thermal effect of light on skin is often critical to track physiological parameters and control light delivery. However, accurate measurement of light-induced thermal effects is challenging because conventional sensors cannot be placed on the skin without obstructing light delivery. Here, we report a wearable optoelectronic patch integrated with a transparent nanowire sensor that provides light delivery and thermal monitoring at the same location. We achieve fabrication of a transparent silver nanowire network with >92% optical transmission that provides thermoresistive sensing of skin temperature. By integrating the sensor in a wireless optoelectronic patch, we demonstrate closed-loop regulation of light delivery as well as thermal characterization of blood flow. This light delivery and thermal monitoring approach may open opportunities for wearable devices in light-based diagnostics and therapies.

Evolution of nanostructured skin patches towards multifunctional wearable platforms for biomedical applications

“…[29][30][31] Recently, a functionalized poly(acrylamide)-based hydrogel was used to formulate a soft interface between wearable electronic devices and human skin, 32 i.e., poly(3,4-ethylenedioxythiophene) (PEDOT)-reinforced laser-irradiated graphene as hetero-structured 3D transducers in a flexible skin patch biosensor. 33 Many advanced skin patches such as pulse oximetry sensing patches with ultralow power consumption, 34 multifunctional hybrid skin patches, 35 textile sensor patches for sweat analysis, 36,37 stress monitoring patches, 38 blood pressure sensing patches, 8 self-powered smart patches, 39 and optoelectronic skin patch 40 have been successfully produced. A PubMed® and EspaceNET search for the term "electronic skin patches" in the title/abstract of peer-review papers demonstrated the exponential increase in the research over the past ten years into the development of these versatile materials for biomedical applications (Fig.…”

Simple Recycling of Ag+, Surfactant, and Solvent for Repeatable Synthesis of Silver Nanowires for Applications as Flexible Transparent Heaters

“…Flexible and wearable electronic devices have drawn enormous attention in various fields such as touch panels, − transparent heaters, − health monitoring sensors, − air filters, fuel cells, supercapacitors, and color changing soft robotics. , Among several candidates to build such devices, silver nanowires (AgNWs) are generally considered to hold great potential to achieve excellent optical, electrical, and mechanical performance. − As a basic component, transparent conductive electrodes (TCEs) made of AgNWs are now reportedly to show higher transmittance and lower sheet resistance than commercial TCEs made of indium tin oxide (ITO) ,, and much better resistance against damage caused by deformation like bending and stretching. Bulk copper is much cheaper than silver, and applications including TCEs, touch panels, solar cells, and wearable heaters based on copper nanowires (CuNWs) have been reported.…”

Optochemical control of Cu(i) homeostasis in mammalian cells

“…This preliminary study on light-controlled inhibition of the coppercontaining enzyme showed unequivocally that adverse effects resulting from the removal of metal centers from metalloenzymes can be avoided when the photocaged chelators are activated locally by light. Tissue-implantable and wirelessly programmable optoelectronic devices were developed by Ho and co-workers 24,25 and it was shown that these devices can be used to selectively and locally activate various light-sensitive molecules including our studied photocaged chelators in target tissues or organs.…”