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The successful implementation of bioelectronic devices attached to living organism hinges on a number of material and device characteristics, including not only electrical and mechanical performances to gather physiological signals from living organism thus enabling status monitoring, but also permeability or breathability for gas/nutrient exchange between living organisms and surroundings to ensure minimum perturbation of the intrinsic biological function. However, most bioelectronic devices built on planar polymeric substrates, such as polydimethylsiloxane (PDMS), polyurethane (PU), and polyimide (PI), lack efficient gas permeability, which may hinder the emission of volatile compounds from the surface of living organism, affecting the natural metabolism and reducing the comfort of wearing. Thus, achieving permeability or breathability in bioelectronic devices is a significant challenge. Currently, the devices made of gas-permeable materials with porous structures, that combine electronic components with daily garments, such as fibric and textile, offer exciting opportunities for breathable electronics. In this review, several types of gas-permeable materials with their synthesis and processing routes are outlines. Then, two methods for measuring water vapor transmission rate of materials are discussed in depth. Finally, recent progress in the use of gas-permeable materials for the applications of plant- and skin-attached electronics is summarized systematically. [ABSTRACT FROM AUTHOR]

Understanding longterm deep tissue damage caused by UV radiation is imperative for ensuring the health and safety of living organisms that are regularly exposed to radiation sources. While existing UV dosimeters can quantify the cumulative amount of radiation to which an organism is exposed, these sensors cannot reveal the presence and extent of internal tissue damage caused by such exposure. Here we describe a method that uses conducting polymer tattoos to detect UV radiation-induced deep tissue damage in living organisms using bioimpedance analysis (BIA), which allows for noninvasive, real-time measurements of body composition and point-of-care assessment of clinical condition. To establish a performance baseline for this method, we quantify the effects of UVA radiation on live plant leaves. Low-energy UVA waves penetrate further into biological tissue, as compared to UVB, UVC and ionizing radiation, and cause longlasting deep tissue damage that cannot be immediately and readily detected using surface-sensitive techniques, such as photogrammetry and epidermal sensors. We show that single-frequency bioimpedance analysis allows for sensitive, real-time monitoring of UVA damage: as UVA dose increases, the bioimpedance of a plant leaf measured at a frequency of 1 kHz linearly decreases until the extent of radiation damage saturates and the specimen is effectively necrotized. We establish a strong correlation between radiation fluence, internal biological damage and the bioimpedance signal measured using our conducting polymer tattoos, which supports the efficacy of our method as a new type of internal biodosimetry. • Vapor-printed conducting polymer tattoos allow for noninvasive bioimpedance measurements on living plants. • Single-frequency bioimpedance analysis quantitatively reveals the extent of deep tissue damage caused by UVA exposure. • A linear correlation between internal biological damage and the bioimpedance signal from vapor-printed tattoos is proven. [ABSTRACT FROM AUTHOR]