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Abstract Integrating tactile feedback through haptic interfaces enhances experiences in virtual and augmented reality. However, electrotactile systems, which stimulate mechanoreceptors directly, often yield inconsistent tactile results due to variations in pressure between the device and the finger. In this study, we present the integration of a transparent electrotactile screen with pressure-sensitive transistors, ensuring highly consistent quantitative haptic sensations. These transistors effectively calibrate tactile variations caused by touch pressure. Additionally, we explore remote-distance tactile stimulations achieved through the interference of electromagnetic waves. We validated tactile perception using somatosensory evoked potentials, monitoring the somatosensory cortex response. Our haptic screen can stimulate diverse electrotactile sensations and demonstrate various tactile patterns, including Morse code and Braille, when integrated with portable smart devices, delivering a more immersive experience. Furthermore, interference of electric fields allows haptic stimulation to facilitate diverse stimulus positioning at lower current densities, extending the reach beyond direct contact with electrodes of our screen.

Abstract Wearable skin-contacting devices are extensively studied for their ability to provide convenient and safe health monitoring. A key aspect that controls their performance are the properties of the device electrodes. Optimizing electrode structure, and the materials they are made from, can improve device functionality. Here, we discuss the various properties required for optimal electrode performance, including mechanical, electrical, and biocompatible factors. To address these challenges, we consider alteration of electrode structure, the development of flexible or soft conductive materials, and the creation of hybrid structures. Additionally, the integration of artificial intelligence is proposed as a promising direction to achieve smart devices. As well as outlining essential characteristics for high-performance wearable skin devices we also offer insight into possible future applications.

Abstract 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.

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.

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.

Glaucoma causes irreversible vision loss due to optic nerve damage and retinal cell degeneration. Since high intraocular pressure (IOP) is a major risk factor for glaucoma development, accurate IOP measurement is crucial, especially intravitreal IOP affecting the optical nerve and cells. However, conventional methods have limits in selectively and directly detecting local retina pressure. Here, we present continuous measurements of local IOP values in the anterior chamber and vitreous chamber of living animals using minimally invasive probes with pressure-sensitive transistors. After inducing glaucoma in animal models, we compared the local IOP distribution between normal and glaucomatous eyes. We also compared IOP values detected in the cornea using tonometry measurements. Our findings revealed that glaucoma induced higher IOP in the vitreous chamber than in the anterior chamber, indicating that measuring IOP in the vitreous chamber is key to the glaucoma model. This progress offers future directions for diagnosis and treatment of glaucoma. [ABSTRACT FROM AUTHOR]