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The high crystallinity and sophisticated hierarchical architecture of native animal silk endow it with comprehensive mechanical properties that are superior to those of most synthetic fibers. However, these features also make the direct exfoliation of silk nanofibrils (SNFs) highly challenging. On the other hand, silk‐based materials prepared by conventional method (i.e., through silk fibroin aqueous solution) are usually weak, so the preparation methods based on SNFs have attracted much attention in recent years. Herein, a facile and environmentally friendly route is developed to directly exfoliate SNFs from natural Bombyx mori silkworm silk via ammonium persulfate oxidation followed by ultrasonication. The obtained SNFs have a high yield (nearly 40%) and are well dispersed in water in a wide pH range, so they can act as a good starting material to prepare subsequent silk‐based materials. The main application of the SNFs demonstrated in this article is a curcumin (Cur)/SNFs hydrogel as wound dressing. In vivo experimental results show that the Cur/SNFs hydrogel significantly enhanced the healing rate of wounds on diabetic mice. Therefore, the preparation method developed in this study provides an efficient way to produce SNFs, which have great potential for a wide range of applications, including as wound dressings for diabetics. [ABSTRACT FROM AUTHOR]

Generating highly organized skeletal muscle tissues that mimics the cellular alignment, maturation, and contraction of native skeletal muscle remains a challenge in disease modeling and regenerative therapies. Existing methodologies are constrained by complexity in fabrication and difficulty in achieving aligned 3D myofibers. Here, a functional skeletal muscle organoid‐on‐a‐chip (SMO) is engineered by establishing mechanical boundary constraints at either end of the cell‐laden extracellular matrix hydrogel within polydimethylsiloxane microstructures to promote the formation of an anisotropic biophysical microenvironment in tissues. The linearly aligned tissue, featuring multinucleated myofibers with distinct cross‐striations, exhibited a positive force‐frequency relationship and stable calcium transients under electrical stimulation. SMOs applicability is demonstrated by systematically evaluating muscle response to varying degrees of intermittent hypoxia. Murine‐ or human‐derived SMOs revealed that, with increasing hypoxia severity, muscles transitioned from a compensatory phase‐characterized by enhanced contractile function, vacuolation and hypertrophic‐like changes in myofibers, fiber type switching, and metabolic shift, to a decompensatory stage, paralleling in vivo muscle responses and highlighting interspecies differences. Human‐derived SMOs are also utilized to assess self‐repair capabilities and pharmaceuticals protective effects on damaged muscle. Together, the platform, with its simplicity of operation and reliable phenotypic readouts, demonstrates significant potential for future disease modeling and regenerative therapies. [ABSTRACT FROM AUTHOR]

A small volume tube-type CO2 sensor was fabricated, which was based on the solid electrolyte material of NASICON prepared by using inorganic salt as raw material. As a sol–gel process was employed, the synthesizing temperature and time were reduced to 800 °C and 8 h, respectively. The resulted NASICON was characterized by XRD, IR, TEM and ion conductivity measurement. Within a wide range of CO2 volume ratio concentration from 100 to 10,000 ppm, the output electromotive force (EMF) of the sensor followed Nernst equation well, and its response and recovery time were less than 15 and 28 s, respectively. The experiments indicated that there was little influence on the sensor characteristics from water vapor, CH4 and CO, which could be attributed to the choice of the suitable binary carbonate electrode and the use of the active carbon cap in package. [Copyright &y& Elsevier]