Recently, wearable electronics for health monitoring have been demonstrated with considerable benefits for early-stage disease detection. This paper reports a flexible, bending-insensitive, bio-compatible and lightweight respiration sensor. The sensor consists of highly oriented carbon nanotube (HO-CNT) films embedded between electro-spun polyacrylonitrile (PAN) layers. By aligning carbon nanotubes between the PAN layers, the sensor exhibits a high sensitivity towards airflow (340 mV/(m/s)) and excellent flexibility and robustness. In addition, the HO-CNT sensor is insensitive to mechanical bending, making it suitable for wearable applications. We successfully demonstrated the attachment of the sensor to the human philtrum for real-time monitoring of the respiration quality. These results indicate the potential of HO-CNT flow sensor for ubiquitous personal health care applications.

Tantalum carbide (TaC), hafnium carbide (HfC), and Ta-Hf-C mixed coatings with and without a gold (Au) interlayer were deposited on 316LVM steel substrates by the magnetron cosputtering technique in order to improve the corrosion resistance of steel substrates in a simulated biological fluid. To study the effect of the gold interlayer on pitting corrosion, the different systems were placed in contact with Ringer’s solution at pH 7.4 and a temperature of 37°C. The electrochemical properties of the coatings were determined using polarization curves. Subsequently, the surface morphologies were observed using scanning electron microscopy (SEM) in order to analyze the corrosion processes on the different surfaces. The gold interlayer was found to significantly improve the electrochemical properties of the system, showing a decrease in the pitting corrosion and deterioration rate, while it is expected that the binary and ternary carbides provide mechanical stability to the bilayers protecting the gold.

Materials used in biomedicine for purposes of long-time stay inside the body presents diverse sort of problems like cytotoxicity, wear, biocompatibility, and ion liberation along time. This paper presents the characterization of corrosion-wear combined phenomena on Nb₂O₅, TiO₂, and Nb₂O₅ + TiO₂ coatings with future applications as biomaterials. After the films’ production process using magnetron sputtering technique, they were characterized through an optic, scanning electron, and atomic force microscopy to evaluate their morphology, structure, and surface damage suffered by the synergy between wear and corrosion phenomena. The life in service of the implant was evaluated in terms of the coating behavior against inside body conditions like charge, wear, and electrochemical degradation. This test was made with electrochemical measurements in simulated biological fluid combined with the wear characterization implementing a potentiostat and a tribometer in a linear wear configuration with a bone pin. As a result, the different electrochemical responses of the films were evidenced by polarization curves and equivalent circuits of the systems. The coefficient of friction and surface degradation were also obtained and evaluated. Comparing the properties of the systems, we conclude that TiO₂ coatings have better behavior in terms of the wear-corrosion synergy phenomena while the systems with Nb present pitting corrosion.