The performance and integration density of silicon integrated circuits (ICs) have progressed at an unprecedented pace in the past 60 years. While silicon ICs thrive at low‐power high‐performance ...computing, creating flexible and large‐area electronics using silicon remains a challenge. On the other hand, flexible and printed electronics use intrinsically flexible materials and printing techniques to manufacture compliant and large‐area electronics. Nonetheless, flexible electronics are not as efficient as silicon ICs for computation and signal communication. Flexible hybrid electronics (FHE) leverages the strengths of these two dissimilar technologies. It uses flexible and printed electronics where flexibility and scalability are required, i.e., for sensing and actuating, and silicon ICs for computation and communication purposes. Combining flexible electronics and silicon ICs yields a very powerful and versatile technology with a vast range of applications. Here, the fundamental building blocks of an FHE system, printed sensors and circuits, thinned silicon ICs, printed antennas, printed energy harvesting and storage modules, and printed displays, are discussed. Emerging application areas of FHE in wearable health, structural health, industrial, environmental, and agricultural sensing are reviewed. Overall, the recent progress, fabrication, application, and challenges, and an outlook, related to FHE are presented.
Flexible hybrid electronics (FHE) with applications in wearable health, structural health, and industrial, environmental, and agricultural sensing are reviewed. The recent progress, fabrication, application, and challenges, and an outlook, relating to FHE are presented with a focus on the fundamental building blocks of FHE systems: printed sensors and circuits, thinned silicon integrated circuits, printed antennas, printed energy harvesting and storage modules, and printed displays.
Pulse oximetry is a ubiquitous non-invasive medical sensing method for measuring pulse rate and arterial blood oxygenation. Conventional pulse oximeters use expensive optoelectronic components that ...restrict sensing locations to finger tips or ear lobes due to their rigid form and area-scaling complexity. In this work, we report a pulse oximeter sensor based on organic materials, which are compatible with flexible substrates. Green (532 nm) and red (626 nm) organic light-emitting diodes (OLEDs) are used with an organic photodiode (OPD) sensitive at the aforementioned wavelengths. The sensor's active layers are deposited from solution-processed materials via spin-coating and printing techniques. The all-organic optoelectronic oximeter sensor is interfaced with conventional electronics at 1 kHz and the acquired pulse rate and oxygenation are calibrated and compared with a commercially available oximeter. The organic sensor accurately measures pulse rate and oxygenation with errors of 1% and 2%, respectively.
The aim of this study was to assess – for the first time – the occurrence and distribution of microplastics (MPs) in the gastrointestinal tracts (GITs) of a marine commercial fish species (
...Micropogonias furnieri
) from the Bahía Blanca Estuary (BBE) in Argentina, and to evaluate fish potential associated stress. In order to do this, juveniles were sampled using artisanal fishing arts at two sampling locations. Basic measurements of individual fish were taken (total length, total weight, weight of the liver) and GITs were subsequently removed, digested with 30% H
2
O
2
for 5 days at 60°C, filtered on Whatman paper and then dried. Samples were observed with a stereomicroscope, and it was demonstrated that 100% of the individuals contained microplastic particles in their GITs. In total, 241 microplastic particles were removed from the GITs of all fish. They were categorized as fibers (60.8%), pellets (28.9%), fragments (8.6%) and laminas (1.4%), and they ranged in size from 0.98 to > 5 mm. The average number of particles per fish was higher than that reported in previous global marine studies. Moreover, a positive correlation between the number of MPs per fish and hepatosomatic index was found, suggesting a probable stress in their health condition. These findings provide the first and southernmost evidence of microplastic contamination in biota from the Argentinean sea, which is found in the South Atlantic sea.
A flexible organic reflectance oximeter array Khan, Yasser; Han, Donggeon; Pierre, Adrien ...
Proceedings of the National Academy of Sciences - PNAS,
11/2018, Letnik:
115, Številka:
47
Journal Article
Recenzirano
Odprti dostop
Transmission-mode pulse oximetry, the optical method for determining oxygen saturation in blood, is limited to only tissues that can be transilluminated, such as the earlobes and the fingers. The ...existing sensor configuration provides only singlepoint measurements, lacking 2D oxygenation mapping capability. Here, we demonstrate a flexible and printed sensor array composed of organic light-emitting diodes and organic photodiodes, which senses reflected light from tissue to determine the oxygen saturation. We use the reflectance oximeter array beyond the conventional sensing locations. The sensor is implemented to measure oxygen saturation on the forehead with 1.1% mean error and to create 2D oxygenation maps of adult forearms under pressure-cuff–induced ischemia. In addition, we present mathematical models to determine oxygenation in the presence and absence of a pulsatile arterial blood signal. The mechanical flexibility, 2D oxygenation mapping capability, and the ability to place the sensor in various locations make the reflectance oximeter array promising for medical sensing applications such as monitoring of real-time chronic medical conditions as well as postsurgery recovery management of tissues, organs, and wounds.
Advances in wireless technologies, low‐power electronics, the internet of things, and in the domain of connected health are driving innovations in wearable medical devices at a tremendous pace. ...Wearable sensor systems composed of flexible and stretchable materials have the potential to better interface to the human skin, whereas silicon‐based electronics are extremely efficient in sensor data processing and transmission. Therefore, flexible and stretchable sensors combined with low‐power silicon‐based electronics are a viable and efficient approach for medical monitoring. Flexible medical devices designed for monitoring human vital signs, such as body temperature, heart rate, respiration rate, blood pressure, pulse oxygenation, and blood glucose have applications in both fitness monitoring and medical diagnostics. As a review of the latest development in flexible and wearable human vitals sensors, the essential components required for vitals sensors are outlined and discussed here, including the reported sensor systems, sensing mechanisms, sensor fabrication, power, and data processing requirements.
Flexible and wearable medical devices with applications in human vital signs monitoring are reviewed. A systemic review of the underlying sensing principle, fabrication, data processing, and power requirements of the biosensors is provided. Body temperature, heart rate, respiration rate, blood pressure, pulse oxygenation, and blood glucose sensors are emphasized, as they are ubiquitous in both fitness monitoring and medical diagnostics.
This paper reports on the design and operation of a flexible power source integrating a lithium ion battery and amorphous silicon solar module, optimized to supply power to a wearable health ...monitoring device. The battery consists of printed anode and cathode layers based on graphite and lithium cobalt oxide, respectively, on thin flexible current collectors. It displays energy density of 6.98 mWh/cm(2) and demonstrates capacity retention of 90% at 3C discharge rate and ~99% under 100 charge/discharge cycles and 600 cycles of mechanical flexing. A solar module with appropriate voltage and dimensions is used to charge the battery under both full sun and indoor illumination conditions, and the addition of the solar module is shown to extend the battery lifetime between charging cycles while powering a load. Furthermore, we show that by selecting the appropriate load duty cycle, the average load current can be matched to the solar module current and the battery can be maintained at a constant state of charge. Finally, the battery is used to power a pulse oximeter, demonstrating its effectiveness as a power source for wearable medical devices.
Human skin is equipped with slow adapting (SA) and fast adapting (FA) capabilities simultaneously. To mimic such functionalities, elaborately designed devices have been explored by integrating ...multiple sensing elements or adopting multimode sensing principles. However, the complicated fabrication, signal mismatch of different modules, complex operation, and high power‐consumption hinder their widespread applications. Here, a new type of single‐mode and self‐powered mechanoreceptor that can mimic both SA and FA via seamless fusion of complementary while compatible potentiometric and triboelectric sensing principles is reported. The resultant potentiometric–triboelectric hybridized mechanoreceptor exhibits distinctive features that are hard to achieve via currently existing methods, including single‐mode output (only voltage signal), greatly simplified operation (single‐measurement setup), ultralow power‐consumption (<1 nW), self‐adaptive response behavior, and good capability for resolving complex stimuli. Diverse mechanical characteristics, including magnitude, duration, frequency, applying and releasing speed, can be well interpreted with this single‐mode and self‐powered mechanoreceptor. Its promising application for monitoring object manipulations with a soft robotic gripper is explored. Furthermore, the versatility of the mechanoreceptor for resolving complex stimuli in diverse daily scenarios is demonstrated. This work presents a new design that will significantly simplify the fabrication/operation and meanwhile boost the functionality/energy‐efficiency of future electronic devices and smart systems.
A new potentiometric–triboelectric hybridized mechanotransduction mechanism is proposed to create single‐mode, self‐adapting, and self‐powered artificial mechanoreceptors. Such mechanoreceptors enable complex mechanical stimuli to be resolved with greatly simplified fabrication/operation and enhanced functionality/energy‐efficiency. The promising applications of the mechanoreceptors in monitoring object manipulation and detecting complex stimuli in diverse practical scenarios of daily life is explored.
Microplastics (MPs) are ubiquitous contaminants of great concern for the environment. MPs' presence and concentration in the air, soil, marine, and freshwater environments have been reported as a ...matter of priority in recent years. This review addresses the current knowledge of the main pathways of MPs in air, soil, and freshwater reservoirs in order to provide an integrated understanding of their behaviors in the continental environment. Therefore, MPs' occurrence (as particle counts), sources, and how their features as shape, size, polymer composition, and density could influence their transport and final sink were discussed. Wind resuspension and atmospheric fallout, groundwater migration, runoff from catchments, and water flow from rivers and effluents were pointed as the principal pathways. MPs' size, shape, polymer composition, and density interact with environmental variables as soil structure and composition, precipitation, wind, relative humidity, water temperature, and salinity. Sampling designs for MPs research should further consider soil characteristics, climate variability and extreme events, time lag and grasshopper effects, morphological and hydrological features of aquatic systems, and water currents, among others. Furthermore, long-term monitoring and lab experiments are still needed to understand MPs' behavior in the environment. This information will provide a unified understanding of the continental MPs pathways, including the key main findings, knowledge gaps, and future challenges to understand this emerging contaminant.
Display omitted
•Continental MPs' presence and pathways in air, soils, and freshwater were addressed.•Atmospheric fallout, runoff, groundwater migration, and hydrodynamics are the main pathways.•MPs size, shape, polymer composition, and density interact with environmental variables.•Long-term monitoring and interdisciplinary research are still needed.
Electronic skins (e‐skins) that mimic the thermosensation and mechanosensation functionalities of natural skin are highly desired for the emerging fields of prosthetics and robotics. Advances in the ...materials and architecture of e‐skins have been made; nevertheless, sensing mechanism innovations are rarely explored. Here, inspired by the skin sensory behaviors, a single potentiometric sensing scheme for both thermosensation and mechanosensation functionalities are presented. Through careful materials selection, component optimization, and structure configuration, the coupling effect between thermosensation and mechanosensation can be significantly minimized. Such a potentiometric sensing scheme enables one to create a new class of energy‐efficient e‐skin with distinctive characteristics that are highly analogous to those of natural human skin. The e‐skin reported here features ultralow power consumption (at nanowatt level), greatly simplified operation (only voltage output), ultrahigh sensitivity (non‐contact sensing capability), all‐solution‐processing fabrication, and, more importantly, good capability for simultaneous monitoring/mapping of both thermal and mechanical stimulations. In addition to proposing a new sensory mechanism, integration of the dual‐functional e‐skin with a soft robotic gripper for object manipulation is demonstrated. The presented concise yet efficient sensing scheme for both thermosensation and mechanosensation opens up previously unexplored avenues for the future design of skin prosthetics, humanoid robotics, and wearable electronics.
A novel e‐skin for both thermosensation and mechanosensation based on a single potentiometric sensing mechanism is reported. Such potentiometric e‐skin features ultralow power consumption, greatly simplified operation, all‐solution‐processing fabrication, and good capability for simultaneous mapping of both thermal and mechanical stimulations. This innovative sensing scheme provides a concise yet efficient design philosophy for future skin prosthetics and humanoid robotics.
The interfacing of soft and hard electronics is a key challenge for flexible hybrid electronics. Currently, a multisubstrate approach is employed, where soft and hard devices are fabricated or ...assembled on separate substrates, and bonded or interfaced using connectors; this hinders the flexibility of the device and is prone to interconnect issues. Here, a single substrate interfacing approach is reported, where soft devices, i.e., sensors, are directly printed on Kapton polyimide substrates that are widely used for fabricating flexible printed circuit boards (FPCBs). Utilizing a process flow compatible with the FPCB assembly process, a wearable sensor patch is fabricated composed of inkjet‐printed gold electrocardiography (ECG) electrodes and a stencil‐printed nickel oxide thermistor. The ECG electrodes provide 1 mVp–p ECG signal at 4.7 cm electrode spacing and the thermistor is highly sensitive at normal body temperatures, and demonstrates temperature coefficient, α ≈ –5.84% K–1 and material constant, β ≈ 4330 K. This sensor platform can be extended to a more sophisticated multisensor platform where sensors fabricated using solution processable functional inks can be interfaced to hard electronics for health and performance monitoring, as well as internet of things applications.
A wearable sensor patch is fabricated by directly interfacing inkjet‐printed gold electrocardiography electrodes and a stencil‐printed nickel oxide thermistor to silicon integrated circuits. This direct printing technique, which is fully compatible with flexible printed circuit board assembly process, is promising for health and performance monitoring, as well as internet of things applications.