A Coiled Carbon Nanotube Yarn-Integrated Surface Electromyography System To Monitor Isotonic and Isometric Movements

Mandrel-free fabrication of giant spring-index and stroke muscles for diverse applications

Methods for making high-spring-index polymer fiber or yarn muscles have required expensive fabrication by wrapping around a mandrel, which limits their practical applications. We demonstrate an inexpensive mandrel-free method for making polymer muscles that can have a spring index of >50 and a contractile tensile stroke exceeding 97%. This method enables the spring index to be varied along a muscle's length by varying the plying twist, resulting in muscles that transition between homochiral and heterochiral when either heated or cooled. We demonstrate use of these polymer muscles for robots and environmentally driven comfort-adjusting jackets. This mandrel-free method was used to make high-spring-index carbon nanotube yarns for mechanical energy harvesters, self-powered strain sensors, and solvent-driven and electrochemically driven artificial muscles.

Advancements in Textile-Based sEMG Sensors for Muscle Fatigue Detection: A Journey from Material Evolution to Technological Integration

Textile-based surface electromyography (sEMG) electrodes have emerged as a prominent tool in muscle fatigue assessment, marking a significant shift toward innovative, noninvasive methods. This review examines the transition from metallic fibers to novel conductive polymers, elastomers, and advanced material-based electrodes, reflecting on the rapid evolution of materials in sEMG sensor technology. It highlights the pivotal role of materials science in enhancing sensor adaptability, signal accuracy, and longevity, crucial for practical applications in health monitoring, while examining the balance of clinical precision with user comfort. Additionally, it maps the global sEMG research landscape of diverse regional contributors and their impact on technological progress, focusing on the integration of Eastern manufacturing prowess with Western technological innovations and exploring both the opportunities and challenges in this global synergy. The integration of such textile-based sEMG innovations with artificial intelligence, nanotechnology, energy harvesting, and IoT connectivity is also anticipated as future prospects. Such advancements are poised to revolutionize personalized preventive healthcare. As the exploration of textile-based sEMG electrodes continues, the transformative potential not only promises to revolutionize integrated wellness and preventive healthcare but also signifies a seamless transition from laboratory innovations to real-world applications in sports medicine, envisioning the future of truly wearable material technologies.

Molecular dynamics simulation study on the binding mechanism between carbon nanotubes and RNA-dependent RNA polymerase

Carbon nanotubes (CNTs) have potential prospects in disease treatment, so it is of great significance to study CNTs as the possible inhibitors of RNA-dependent RNA polymerase (RdRp). Through the way of using the RdRp of SARS-COV-2 as a model, five armchair single-walled carbon nanotubes (SWCNTs) (namely Dn, which stands for CNTs (n, m = n), n = 3-7) and RdRp have been selected to study the interactions by means of molecular docking and molecular dynamics simulation. After five SWCNT-RdRp complex systems have been subjected to the molecular dynamics simulations of 100 ns, and Molecular Mechanics Poisson - Boltzmann Surface Area (MMPBSA) has been used to calculate the binding free energy, it is found that the binding free energy of the D6 system (-189.541 kJ/mol) is significantly higher than that of the other four systems, and most of the amino acids with strong positive effects on binding are usually basic amino acids. What's more, in the further investigation of the specific interaction mechanism between CNT (6,6) and RdRp, it is revealed that the three amino acid residues LYS545, ARG553 and ARG555 located in the nucleoside triphosphate (NTP) entry channel all have strong effects. In addition, it is also observed that when ARG555 has been inserted into SWCNT, a stable structure will be formed, which will break the original NTP entry channel structure and inhibit virus replication. Therefore, it can be concluded that certain specific types of SWCNT, such as CNT (6,6), could be potential small molecule inhibitors in the treatment of coronavirus.Communicated by Ramaswamy H. Sarma.

Recent Advances in Carbon Nanotube-Based Energy Harvesting Technologies

There has been enormous interest in technologies that generate electricity from ambient energy such as solar, thermal, and mechanical energy, due to their potential for providing sustainable solutions to the energy crisis. One driving force behind the search for new energy-harvesting technologies is the desire to power sensor networks and portable devices without batteries, such as self-powered wearable electronics, human health monitoring systems, and implantable wireless sensors. Various energy harvesting technologies have been demonstrated in recent years. Among them, electrochemical, hydroelectric, triboelectric, piezoelectric, and thermoelectric nanogenerators have been extensively studied because of their special physical properties, ease of application, and sometimes high obtainable efficiency. Multifunctional carbon nanotubes (CNTs) have attracted much interest in energy harvesting because of their exceptionally high gravimetric power outputs and recently obtained high energy conversion efficiencies. Further development of this field, however, still requires an in-depth understanding of harvesting mechanisms and boosting of the electrical outputs for wider applications. Here, various CNT-based energy harvesting technologies are comprehensively reviewed, focusing on working principles, typical examples, and future improvements. The last section discusses the existing challenges and future directions of CNT-based energy harvesters.