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Biomedical electronic devices have enormous benefits for healthcare and quality of life. Still, the long‐term working of those devices remains a great challenge due to the short life and large volume of conventional batteries. Since the nanogenerators (NGs) invention, they have been widely used to convert various ambient mechanical energy sources into electrical energy. The self‐powered technology based on NGs is dedicated to harvesting ambient energy to supply electronic devices, which is an effective pathway to conquer the energy insufficiency of biomedical electronic devices. With the aid of this technology, it is expected to develop self‐powered biomedical electronic devices with advanced features and distinctive functions. The goal of this review is to summarize the existing self‐powered technologies based on NGs and then review the applications based on self‐powered technologies in the biomedical field during their rapid development in recent years, including two main directions. The first is the NGs as independent sensors to converts biomechanical energy and heat energy into electrical signals to reflect health information. The second direction is to use the electrical energy produced by NGs to stimulate biological tissues or powering biomedical devices for achieving the purpose of medical application. Eventually, we have analyzed and discussed the remaining challenges and perspectives of the field. We believe that the self‐powered technology based on NGs would advance the development of modern biomedical electronic devices.

A miniature Fabry–Perot interferometric acoustic sensor with an ultra-high pressure sensitivity was constructed by using approximately 13 layers of graphene film as the diaphragm. The extremely thin diaphragm was transferred onto the endface of a ferrule, which had an inner diameter of 125 μm, and van der Waals interactions between the graphene diaphragm and its substrate created a low finesse Fabry–Perot interferometer with a cavity length of 98 μm. Acoustic testing demonstrated a pressure-induced deflection of 2380 nm kPa−1 and a noise equivalent acoustic signal level of ~2.7 mPa/Hz1/2 for a 3 dB bandwidth with a center frequency of 15 kHz. The sensor also exhibited a dynamic frequency response between 1 and 20 kHz, which conformed well to the result obtained by a reference microphone. The use of a suspended graphene diaphragm has potential applications in highly sensitive pressure/acoustic sensors.

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Toxicity is one of the major reasons for failure in drug development. Zebrafish, as an ideal vertebrate model, could also be used to evaluate drug toxicity. In this study, we aimed to show the predictability and highlight novel findings of toxicity in zebrafish model. Seven anticancer compounds, including triptolide (TP), gambogic acid (GA), mycophenolic acid (MPA), curcumin, auranofin, thalidomide, and taxol, were assessed in zebrafish for their toxicity. Three compounds (GA, TP, and taxol) showed highest acute lethality, with 50% lethal concentration ≈ 1 μmol/L. Missing tails, severe pericardial edema, and enlarged yolk sacs were observed in MPA-treated embryos. The development of pectoral fins was severely disturbed in thalidomide-, GA-, and TP-treated embryos. Bradycardia was observed in MPA- and thalidomide-treated groups. Our findings suggested that the zebrafish are a good model for toxicity assessment of anticancer compounds.

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Ammonia borane (AB) has been considered as one of the most attractive chemical hydrides for on-board hydrogen storage due to its small molecular weight, high hydrogen storage density, high stability, and nontoxicity. However, the utilization of AB is still restricted by the slow kinetics of H2 release at low temperatures (<85 °C) and simultaneous generation of volatile byproducts. Herein, a new catalytic strategy involving palladium (Pd) catalysis and nanoconfinement in natural halloysite nanotubes (HNTs) for pyrolysis releasing H2 from AB is developed. The results show that AB can be encapsulated into HNTs channels and coated on the surface of HNTs with a uniform nanolayer. The synergetic catalysis of HNTs and ultrasmall Pd nanocatalysts (∼1.4 nm) and the nanoconfinement of AB immobilized on HNTs are beneficial to improving catalytic activities for pyrolysis of AB, which not only avoids emitting byproducts of ammonia, diborane, and borazine but also inhibits usual foaming and expansion of AB during the dehydrogenation process. Meanwhile, the nanoconfinement of AB immobilized on HNTs results in improved kinetics of H2 release at low temperatures of 60 °C, while no H2 evolves from the neat AB at 80 °C. The activation energy of AB@Pd/HNTs is 46 kJ mol–1, which is considerably lower than that of neat AB of 183 kJ mol–1. The results show that natural HNTs can be used as economical and efficient supports for fabrication of AB@Pd/HNTs hydrogen storage composites, and Pd/HNTs can be used as effective catalysts to improve the dehydrogenation properties of AB.