Biointerfaced sensors for biodiagnostics

Biointerfaced sensors have emerged as a new paradigm for medical applications that require an interface and/or intimate contact with biological components/systems such as cells, tissues, and whole organs. This article provides a review of the concept, design, and device characteristics of biointerfaced sensors needed for successful implementation of biodiagnostics and monitoring. It begins by presenting and discussing the different considerations that arise from artificial interfaces with different biological environments. It then explores the main strategies for sensor and material design, while highlighting the required chemistry, structure, and mechanical properties needed to maintain an unperturbed interface with the surrounding biological environment. Finally, the review discusses successful state-of-the-art demonstrations of body monitoring and biodiagnostics, focusing on the brain, heart, muscles, skin, teeth, and other tissues for medical purposes. Insights, perspectives, and recommendations for future research are presented.

Profiles of Volatile Biomarkers Detect Tuberculosis from Skin

Tuberculosis (TB) is an infectious disease that threatens >10 million people annually. Despite advances in TB diagnostics, patients continue to receive an insufficient diagnosis as TB symptoms are not specific. Many existing biodiagnostic tests are slow, have low clinical performance, and can be unsuitable for resource-limited settings. According to the World Health Organization (WHO), a rapid, sputum-free, and cost-effective triage test for real-time detection of TB is urgently needed. This article reports on a new diagnostic pathway enabling a noninvasive, fast, and highly accurate way of detecting TB. The approach relies on TB-specific volatile organic compounds (VOCs) that are detected and quantified from the skin headspace. A specifically designed nanomaterial-based sensors array translates these findings into a point-of-care diagnosis by discriminating between active pulmonary TB patients and controls with sensitivity above 90%. This fulfills the WHO’s triage test requirements and poses the potential to become a TB triage test.

Highly Efficient and Water‐Insensitive Self‐Healing Elastomer for Wet and Underwater Electronics

Integrating self‐healing capabilities into soft electronic devices increases their durability and long‐term reliability. Although some advances have been made, the use of self‐healing electronics in wet and/or (under)water environments has proven to be quite challenging, and has not yet been fully realized. Herein, a new highly water insensitive self‐healing elastomer with high stretchability and mechanical strength that can reach 1100% and ≈6.5 MPa, respectively, is reported. The elastomer exhibits a high (>80%) self‐healing efficiency (after ≈ 24 h) in high humidity and/or different (under)water conditions without the assistance of an external physical and/or chemical triggers. Soft electronic devices made from this elastomer are shown to be highly robust and able to recover their electrical properties after damages in both ambient and aqueous conditions. Moreover, once operated in extreme wet or underwater conditions (e.g., salty seawater), the self‐healing capability leads to the elimination of significant electrical leakage that would be caused by structural damages. This highly efficient self‐healing elastomer can help extend the use of soft electronics outside of the laboratory and allow a wide variety of wet and submarine applications.

A Multifunctional Electronic Skin Empowered with Damage Mapping and Autonomic Acceleration of Self‐Healing in Designated Locations

Integrating self‐healing capabilities into soft electronic devices and sensors is important for increasing their reliability, longevity, and sustainability. Although some advances in self‐healing soft electronics have been made, many challenges have been hindering their integration in digital electronics and their use in real‐world conditions. Herein, an electronic skin (e‐skin) with high sensing performance toward temperature, pressure, and pH levels—both at ambient and/or in underwater conditions is reported. The e‐skin is empowered with a novel self‐repair capability that consists of an intrinsic mechanism for efficient self‐healing of small‐scale damages as well as an extrinsic mechanism for damage mapping and on‐demand self‐healing of big‐scale damages in designated locations. The overall design is based on a multilayered structure that integrates a neuron‐like nanostructured network for self‐monitoring and damage detection and an array of electrical heaters for selective self‐repair. This system has significantly enhanced self‐healing capabilities; for example, it can decrease the healing time of microscratches from 24 h to 30 s. The electronic platform lays down the foundation for the development of a new subcategory of self‐healing devices in which electronic circuit design is used for self‐monitoring, healing, and restoring proper device function.

Self-healing Artificial Electronic Skin Monitors Various Physical and Chemical Variables

Check out the new article about TECH’s work on self-healing sensors at web.

Time-space-resolved origami hierarchical electronics for ultrasensitive detection of physical and chemical stimuli

Recent years have witnessed the thriving progress of flexible and portable electronics, with a very high demand for cost-effective and tailor-made multifunctional devices. Here, we report on an ingenious origami hierarchical sensor array (OHSA) written with conductive ink. Thanks to origami as a controllable hierarchical framework for loading ink material, we have demonstrated that OHSA possesses unique time-space-resolved, high-discriminative pattern recognition (TSR-HDPR) features, qualifying it as a smart sensing device for simultaneous sensing and distinguishing of complex physical and chemical stimuli, including temperature, relative humidity, light and volatile organic compounds (VOCs). Of special importance, OSHA has shown very high sensitivity in differentiating between structural isomers and chiral enantiomers of VOCs – opening a door for a wide variety of unique opportunities in several length scales.