Sensors (Basel)
November 2024
In recent years, skin-mounted devices have gained prominence in personal wellness and remote patient care. However, the rigid components of many wearables often cause discomfort due to their mechanical mismatch with the skin. To address this, we extend the use of the solderable stretchable sensing system (S4) to develop a wireless skin temperature-sensing smart adhesive.
View Article and Find Full Text PDFAchieving large-scale, cost-effective, and reproducible manufacturing of stem cells with the existing devices is challenging. Traditional single-use cell-bag bioreactors, limited by their rigid and single-point sensors, struggle with accuracy and scalability for high-quality cell manufacturing. Here, we introduce a smart bioreactor system that enables multi-spatial sensing for real-time, wireless culture monitoring.
View Article and Find Full Text PDFAlthough many people suffer from sleep disorders, most are undiagnosed, leading to impairments in health. The existing polysomnography method is not easily accessible; it's costly, burdensome to patients, and requires specialized facilities and personnel. Here, we report an at-home portable system that includes wireless sleep sensors and wearable electronics with embedded machine learning.
View Article and Find Full Text PDFRecent advances in wearable technologies have enabled ways for people to interact with external devices, known as human-machine interfaces (HMIs). Among them, electrooculography (EOG), measured by wearable devices, is used for eye movement-enabled HMI. Most prior studies have utilized conventional gel electrodes for EOG recording.
View Article and Find Full Text PDFModern auscultation, using digital stethoscopes, provides a better solution than conventional methods in sound recording and visualization. However, current digital stethoscopes are too bulky and nonconformal to the skin for continuous auscultation. Moreover, motion artifacts from the rigidity cause friction noise, leading to inaccurate diagnoses.
View Article and Find Full Text PDFHotter summers caused by global warming and increased workload and duration are endangering the health of farmworkers, a high-risk population for heat-related illness (HRI), and deaths. Although prior studies using wearable sensors show the feasibility of employing field-collected data for HRI monitoring, existing devices still have limitations, such as data loss from motion artifacts, device discomfort from rigid electronics, difficulties with administering ingestible sensors, and low temporal resolution. Here, this paper introduces a wireless, wearable bioelectronic system with functionalities for continuous monitoring of skin temperature, electrocardiograms (ECG), heart rates (HR), and activities, configured in a single integrated package.
View Article and Find Full Text PDFObstructive sleep apnea (OSA) affects more than 900 million adults globally and can create serious health complications when untreated; however, 80% of cases remain undiagnosed. Critically, current diagnostic techniques are fundamentally limited by low throughputs and high failure rates. Here, we report a wireless, fully integrated, soft patch with skin-like mechanics optimized through analytical and computational studies to capture seismocardiograms, electrocardiograms, and photoplethysmograms from the sternum, allowing clinicians to investigate the cardiovascular response to OSA during home sleep tests.
View Article and Find Full Text PDFAcoustic stethoscopes have demonstrated beneficial factors aiding diagnosis from the doctors with accurate body sounds. Still, the conventional acoustic stethoscopes require a substantial amount of clinical experience and hearing skills for the physicians to accurately diagnose symptoms from abnormal sounds. Especially for cardiopulmonary systems, it is crucial to collect sounds with precision since they contain valuable information in specific frequency ranges for various sounds.
View Article and Find Full Text PDFMotor imagery offers an excellent opportunity as a stimulus-free paradigm for brain-machine interfaces. Conventional electroencephalography (EEG) for motor imagery requires a hair cap with multiple wired electrodes and messy gels, causing motion artifacts. Here, a wireless scalp electronic system with virtual reality for real-time, continuous classification of motor imagery brain signals is introduced.
View Article and Find Full Text PDFSaliva can be used for health monitoring with non-invasive wearable systems. Such devices, including electrochemical sensors, may provide a safe, fast, and cost-efficient way of detecting target ions. Although salivary ions are known to reflect those in blood, no available clinical device can detect essential ions directly from saliva.
View Article and Find Full Text PDFStress has become a significant factor, directly affecting human health. Due to the numerous sources of stress that are inevitable in daily life, effective management of stress is essential to maintain a healthy life. Recent advancements in wearable devices allow monitoring stress levels via the detection of galvanic skin response on the skin.
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2020
Recent advances in flexible materials and wearable electronics offer a noninvasive, high-fidelity recording of biopotentials for portable healthcare, disease diagnosis, and machine interfaces. Current device-manufacturing methods, however, still heavily rely on the conventional cleanroom microfabrication that requires expensive, time-consuming, and complicated processes. Here, we introduce an additive nanomanufacturing technology that explores a contactless direct printing of aerosol nanomaterials and polymers to fabricate stretchable sensors and multilayered wearable electronics.
View Article and Find Full Text PDFSensors that can detect external stimuli and perceive the surrounding areas could offer an ability for soft biomimetic robots to use the sensory feedback for closed-loop control of locomotion. Although various types of biomimetic robots have been developed, few systems have included integrated stretchable sensors and interconnectors with miniaturized electronics. Here, we introduce a soft, stretchable nanocomposite system with built-in wireless electronics with an aim for feedback-loop motion control of a robotic earthworm.
View Article and Find Full Text PDFStress is one of the main causes that increase the risk of serious health problems. Recent wearable devices have been used to monitor stress levels via electrodermal activities on the skin. Although many biosensors provide adequate sensing performance, they still rely on uncomfortable, partially flexible systems with rigid electronics.
View Article and Find Full Text PDFRecent advances in nanomaterials and nano-microfabrication have enabled the development of flexible wearable electronics. However, existing manufacturing methods still rely on a multi-step, error-prone complex process that requires a costly cleanroom facility. Here, we report a new class of additive nanomanufacturing of functional materials that enables a wireless, multilayered, seamlessly interconnected, and flexible hybrid electronic system.
View Article and Find Full Text PDFWireless, flexible, ion-selective electrodes (ISEs) are of great interest in the development of wearable health monitors and clinical systems. Existing film-based electrochemical sensors, however, still have practical limitations due to poor electrical contact and material-interfacial leakage. Here, we introduce a wireless, flexible film-based system with a highly selective, stable, and reliable sodium sensor.
View Article and Find Full Text PDFRecent advancements in electronic packaging and image processing techniques have opened the possibility for optics-based portable eye tracking approaches, but technical and safety hurdles limit safe implementation toward wearable applications. Here, we introduce a fully wearable, wireless soft electronic system that offers a portable, highly sensitive tracking of eye movements (vergence) via the combination of skin-conformal sensors and a virtual reality system. Advancement of material processing and printing technologies based on aerosol jet printing enables reliable manufacturing of skin-like sensors, while the flexible hybrid circuit based on elastomer and chip integration allows comfortable integration with a user's head.
View Article and Find Full Text PDFBlepharospasm (BL) is characterized by involuntary closures of the eyelids due to spasms of the orbicularis oculi muscle. The gold standard for clinical evaluation of BL involves visual inspection for manual rating scales. This approach is highly subjective and error prone.
View Article and Find Full Text PDFRecent advances in biosensors, bioelectronics, and system integration allow the development of wristband-type devices for health and performance monitoring of athletes. Although these devices provide adequate sensing outputs, they suffer from signal loss due to improper contact of a rigid sensor with the skin. In addition, when a rubber band tightly secures the sensor to the skin, the gap between sensor and skin causes inevitable motion artifacts, resulting in corrupted data.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2020
Among the various methods to develop flexible wearable antennas, a serpentine, mesh structure has been a great interest because of its mechanical reliability upon applied strain. However, there is still a significant lack of design guidelines for the open-mesh concept that account for both material and electromagnetic (EM) properties of antennas. In this work, we introduce a comprehensive study of materials, mechanics, fabrication, and system integration for the development of stretchable dipole and patch antennas that have networks of two-dimensional serpentine patterns.
View Article and Find Full Text PDFContinuous cardiac monitoring using electrocardiograms (ECG) provides a range of patient information, essential for making clinical decisions, to healthcare providers. Unfortunately, the clinical standard of ECG recording requires the use of rigid metal electrodes, conductive gels, and wired electronic devices, which often cause skin injuries and health risks for pediatric patients with underdeveloped, fragile skin. Here, we introduce a wireless, soft, comfortable electronic system that obviates the need for skin preparation, electrolyte gels, or aggressive tapes.
View Article and Find Full Text PDFThe spine flexibility creates one of the most significant challenges to proper positioning in radiation therapy of head and neck cancers. Even though existing immobilization techniques can reduce the positioning uncertainty, residual errors (2-3 mm along the cervical spine) cannot be mitigated by single translation-based approaches. Here, we introduce a fully radiotherapy-compatible electro-mechanical robotic system, capable of positioning a patient's head with submillimeter accuracy in clinically acceptable spatial constraints.
View Article and Find Full Text PDFCommercially available health monitors rely on rigid electronic housing coupled with aggressive adhesives and conductive gels, causing discomfort and inducing skin damage. Also, research-level skin-wearable devices, while excelling in some aspects, fall short as concept-only presentations due to the fundamental challenges of active wireless communication and integration as a single device platform. Here, an all-in-one, wireless, stretchable hybrid electronics with key capabilities for real-time physiological monitoring, automatic detection of signal abnormality via deep-learning, and a long-range wireless connectivity (up to 15 m) is introduced.
View Article and Find Full Text PDFMolecular detection and manipulation via nanofluidic systems offers new routes for single-molecule analysis to study epigenetic mechanisms and genetic mutation of disease. For detection of single biological molecule, many types of nanomicrofluidic systems have been utilized. Typically, mechanical tethering, fluidic pressure, chemical interactions, or electrical forces allow controllable attraction, enrichment, confinement, and elongation of target molecules.
View Article and Find Full Text PDFInkjet-printed electronics using metal particles typically lack electrical conductivity and interfacial adhesion with an underlying substrate. To address the inherent issues of printed materials, this Research Article introduces advanced materials and processing methodologies. Enhanced adhesion of the inkjet-printed copper (Cu) on a flexible polyimide film is achieved by using a new surface modification technique, a nanostructured self-assembled monolayer (SAM) of (3-mercaptopropyl)trimethoxysilane.
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