On-skin dry electronics are critical for stably transmitting vital and various electrophysiological signals for diagnostics and the human/machine interface, but they are limited by intrinsically poor compliance. High signal-to-noise ratio (SNR) and long-term monitoring fidelity require dry electrode to be highly adhesive in compensation to maintain the conformable contact. However, enlarged adhesive force between electrode and skin will lead to irritant contact with elevated risk of signal distortion and contamination caused delamination. Herein, we develop a delamination-resistant imperceptible bioelectrode (DrIE) on the merits of relieving deformation-induced stress during body movements and allowing gas permeation for long-term wearing. Furthermore, benefiting from the augmented mechanical compliance and ultralow thickness, the SNR of our electrode in recording electromyogram (EMG) signals retains 35.23 dB and even the adhesive force is down to 0.013 N/cm, considerably improving the fidelity, recyclability, and wearing comfortability. Our strategy of utilizing dynamic polymer chain rearrangements promoted stress relaxation for compliant DrIE proposes a universal route to the robust biointerface for next-generation clinical applications.

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Ferrite nanoparticles have been widely used in the biomedical field (such as magnetic targeting, magnetic resonance imaging, magnetic hyperthermia, etc.) due to their appealing magnetic properties. In tumor acidic microenvironment, ferrite nanoparticles show intrinsic peroxidase-like activities, which can catalyze the Fenton reaction of hydrogen peroxide (H2O2) to produce highly toxic hydroxyl free radicals (•OH), causing the death of tumor cell. Recent progresses in this field have shown that the enzymatic activity of ferrite can be improved via converting external field energy such as alternating magnetic field and near-infrared laser into nanoscale heat to produce more •OH, enhancing the killing effect on tumor cells. On the other hand, combined with other nanomaterials or drugs for cascade reactions, the production of reactive oxygen species (ROS) can also be increased to obtain more efficient cancer therapy. In this review, we will discuss the current status and progress of the application of ferrite nanoparticles in ROS-mediated cancer therapy and try to provide new ideas for this area.

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Recently, rapid advances in flexible strain sensors have broadened their application scenario in monitoring of various mechanophysiological signals. Among various strain sensors, the crack-based strain sensors have drawn increasing attention in monitoring subtle mechanical deformation due to their high sensitivity. However, early generation and rapid propagation of cracks in the conductive sensing layer result in a narrow working range, limiting their application in monitoring large biomechanical signals. Herein, we developed a stress-deconcentrated ultrasensitive strain (SDUS) sensor with ultrahigh sensitivity (gauge factor up to 2.3 × 10 6 ) and a wide working range (0%-50%) via incorporating notch-insensitive elastic substrate and microcrack-tunable conductive layer. Furthermore, the highly elastic amine-based polymer-modified polydimethylsiloxane substrate without obvious hysteresis endows our SDUS sensor with a rapid response time (2.33 ms) to external stimuli. The accurate detection of the radial pulse, joint motion, and vocal cord vibration proves the capability of SDUS sensor for healthcare monitoring and human-machine communications.

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La 1-x Sm x-y Sr y CoO 3-G (LSSC; x=0.475, 0.650, 0.825, y=0.35, 0.40, 0.45) compounds, which have the same compositions as the La 0.7 Sr 0.3 CoO 3-G (LSC) and Sm 0.5 Sr 0.5 CoO 3-G (SSC) mixture (corresponding mole ratio is 3:1, 1:1 and 1:3, respectively), are synthesized through a conventional solid-state reaction and characterized by X-ray diffraction, thermal expansion coefficient, X-ray photoelectron spectrometer and electrical conductivity measurement, as well as the electrochemical impedance spectra and single cell performance measurement. Interestingly, the experimental results reveal that with the linear increase of y in LSSC, the conductivity of the corresponding samples does not alter linearly but reaches a peak when y=0.35, namely, the maximum electrical conductivity enhancing from 2148 S cm-1 (LSC, y=0.30) and 1802 S cm-1 (SSC, y=0.50) to 2750 S cm-1 (y=0.35). In addition, this turning point coincidently corresponds to the structure transition from hexagonal (y=0.35) to orthorhombic (y=0.40). Furthermore, comparing with LSC and SSC, the cathode polarization resistance (R P) decreases by about 50% and 38%, respectively, after employing the LSSC (y=0.40) compound as cathode at 800 o C and 0.21 atm p(O 2), which also leads to an increment

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