No abstract

Herein, a wireless and soft smart contact lens that enables real‐time quantitative recording of cholesterol in tear fluids for the monitoring of patients with hyperlipidemia using a smartphone is reported. This contact lens incorporates an electrochemical biosensor for the continuous detection of cholesterol concentrations, stretchable antenna, and integrated circuits for wireless communication, which makes a smartphone the only device required to operate this lens remotely without obstructing the wearer's vision. The hyperlipidemia rabbit model is utilized to confirm the correlation between cholesterol levels in tear fluid and blood and to confirm the feasibility of this smart contact lens for diagnostic application of cholesterol‐related diseases. Further in vivo tests with human subjects demonstrated its good biocompatibility, wearability, and reliability as a non‐invasive healthcare device.

We measured the electrical activity signals of the heart through vital signs monitoring garments that have textile electrodes in conductive yarns while the subject is in stable and dynamic motion conditions. To measure the electrical activity signals of the heart during daily activities, four types of monitoring garment were proposed. Two experiments were carried out as follows: the first experiment sought to discover which garment led to the least displacement of the textile electrode from its originally intended location on the wearer's body. In the second, we measured and compared the electrical activity signals of the heart between the wearer's stable and dynamic motion states. The results indicated that the most appropriate type of garment sensing-wise was the "cross-type", and it seems to stabilize the electrode's position more effectively. The value of SNR of ECG signals for the "cross-type" garment is the highest. Compared to the "chest-belt-type" garment, which has already been marketed commercially, the "cross-type" garment was more efficient and suitable for heart activity monitoring.

Organic light-emitting diode (OLED) fibers with favorable electroluminescence properties and interconnectable pixel configurations have represented the potential for wearable electronic textile displays. Nevertheless, the current technology of OLED fiber-based textile displays still leaves to be desired due to several challenges, including limited emission area and lack of encapsulation systems. Here we present a fibrous OLED textile display that can attain a large emission area and long-term stability by implementing addressable networks comprised of integrated phosphorescence OLED fibers and by designing multilayer encapsulations. The integrated fiber configuration offers decoupled functional fiber surfaces for an interconnectable 1-dimensional OLED pixel array and a data-addressing conductor. Tailored triadic metal/ultrathin oxide/polymer multilayer enables not only the oxygen/water permeation inhibition but also the controllable conductive channels of dielectric antifuses. Together with reliable bending stability, the long-term operation of OLED textiles in water manifests the feasibility of the present device concept toward water-resistant full-emitting-area fibrous textile displays.

Organoids refer to 3D stem cells that have been developed to model neurological disorders in vitro. Typically, brain and heart organoids have gained interest for their potential to truly mimic the functional ability of real organs. Morphological analysis methods using immunostaining and slicing of the organoids are explored extensively over the past decade to evaluate the structures and functions of organoids. However, the destructiveness of these methods limits real‐time monitoring of the dynamic responses of the organoids. Therefore, electrophysiological functional analysis of organoids with minimally invasive forms can be a key solution to an improved understanding of the nature of complex organoids. Herein, the latest advances in the recording platforms are reviewed and a comprehensive study of considerations regarding electrophysiological factors is provided. Furthermore, current challenges are discussed along with prospects for next‐generation electrophysiological analysis of brain and heart organoids.

No abstract

Electrical stimulation as a therapeutic approach is widely applicable in terms of target tissues or target effects. This method can be an alternative to conventional therapies for patients who are resistant to drugs or are ineligible for surgical operations. In addition, as researchers have actively studied how to adjust the parameters for electrical stimulation in order to improve effectiveness, many patients have already received treatments with electrical stimulation. With respect to devices for electrical stimulation, recent studies are focused on developing reliability for safe and long‐term operations. From the point of view of engineers, a comprehensive understanding of how electrical stimulation modulates the biological system is essential to develop advanced strategies that provide effective therapeutic results. Herein, the fundamental mechanisms for delivering electrical stimulation on biological tissues are reviewed along with the requirements that need to be qualified by the electrodes. Furthermore, the latest advances in electrical stimulation devices are discussed followed by an introduction of representative applications of therapeutic electrical stimulation.

Recently, personalized medical diagnostics and treatments have received significant interest due to the rising demand for reliable, rapid, and cost-effective healthcare services. In the recent development of wearable devices, ways to engineer devices to extend their reliability, minimize the risk of infection, and expand the scope of application have been focused on improving conventional clinical procedures. With the increasing interest in personalized healthcare, wearable devices have received substantial interest because they monitor each physiological parameter for specific clinical interest. These unique bio-parameters of individuals can be recorded from different target organs for the analysis of various functions, ranging from simple bodily movement to clinical treatment. In this review, the recent advances in sensors for recording unique bio-signals from the human body are discussed. Based on each unique bio-signals, a comprehensive analysis of wearable platforms for clinical diagnosis is provided, including subjects such as the selection of materials, device design structure, and application strategies for therapeutic significance. Furthermore, the challenges and future potential direction of modern bio-sensor devices are discussed extensively.