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Biodegradable microswimmers offer great potential for minimally invasive targeted therapy due to their tiny scale, multifunctionality, and versatility. However, most of the reported systems focused on the proof‐of‐concept on the in vitro level. Here, the successful fabrication of facile hydrogen‐powered microswimmers (HPMs) for precise and active therapy of acute ischemic stroke is demonstrated. The hydrogen (H2) generated locally from the designed magnesium (Mg) microswimmer functions not only as a propellant for motion, but also as an active ingredient for reactive oxygen species (ROS) and inflammation scavenging. Due to the continuous detachment of the produced H2, the motion of the microswimmers results in active H2 delivery that allows for enhanced extracellular and intracellular reducibility. With the help of a stereotaxic apparatus device, HPMs were injected precisely into the lateral ventricle of middle cerebral artery occlusion (MCAO) rats. By scavenging ROS and inflammation via active H2, MCAO rats exhibit significant decrease in infarct volume, improved spatial learning and memory capability with minimal adverse effects, demonstrating efficient efficacy on anti‐ischemic stroke. The as‐developed HPMs with excellent biocompatibility and ROS scavenging capability holds great promise for the treatment of acute ischemic stroke or other oxidative stress induced diseases in clinic in the near future. [ABSTRACT FROM AUTHOR]

Micro/nanomotors are revolutionary miniaturized robotic systems capable of converting diverse energy sources, including light, ultrasound, and thermal heat, into mechanical motion. This fascinating research area is emerging and developing at a rapid pace, demonstrating potential in multiple fields. While their locomotion and momentum capabilities have been explored in medical treatments, including microsurgery and diagnosis, the aspect of converting their intrinsic energies into usable forms remains unexplored. Here, we proposed a novel motor based on composite TiO2‐Au nanowires (NWs), powered by a local electric field generated from ultra‐low ultraviolet (UV) irradiation, to serve as an interactive bioelectric interface with a neural cell. Under a light field, the NW motor achieved highly controllable motion in biological environments and reached the targeted neuronal retinal ganglion cells (RGCs) with notable precision. Next, the locally generated electric field was utilized as an electrical stimulus to activate the targeted cell through the calcium ion channel. This is the first study to report on the photoelectric conversion capabilities of a motor being used to provide propulsion force and interactive cues in a biosystem. This motor‐based strategy represents a new approach for the precise and non‐invasive delivery of bioelectrical signals and neuronal activity modulation. [ABSTRACT FROM AUTHOR]

Nanoparticle‐based drug delivery systems with low side effects and enhanced efficacy hold great potential in the treatment of various malignancies, in particular cancer; however, they are still challenging to attain. Herein, an anticancer drug delivery system based on a cisplatin (CDDP) containing nanogel, functionalized with photothermal gold nanorods (GNRs) which are electrostatically decorated with doxorubicin (DOX) is reported. The nanoparticles are formed via the crosslinking reaction of hyaluronic acid with the ancillary anticarcinogen CDDP in the presence of DOX‐decorated GNRs. The nanogel is furthermore cloaked with a cancer cell membrane, and the resulting biomimetic nanocarrier (4T1‐HANG‐GNR‐DC) shows efficient accumulation by homologous tumor targeting and possesses long‐time retention in the tumor microenvironment. Upon near‐infrared (NIR) laser irradiation, in situ photothermal therapy is conducted which further induces hyperthermia‐triggered on‐demand drug release from the nanogel reservoir to achieve a synergistic photothermal/chemo‐therapy. The as‐developed biomimetic nanocarriers, with their dual‐drug delivery features, homotypic tumor targeting and synergetic photothermal/chemo‐therapy, show much promise as a potential platform for cancer treatment. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke, hydrogen-powered microswimmers, inflammation attenuating, minimally invasive therapy, ROS scavenging By scavenging ROS and inflammation via active hydrogen, the microswimmers exhibit an outstanding neuroprotection and ischemia stroke remedy effect, which also hold great promise for the treatment of other oxidative stress-induced diseases in clinical practice. Keywords: acute ischemic stroke; hydrogen-powered microswimmers; inflammation attenuating; minimally invasive therapy; ROS scavenging EN acute ischemic stroke hydrogen-powered microswimmers inflammation attenuating minimally invasive therapy ROS scavenging 1 1 1 05/12/21 20210510 NES 210510 In article number 2009475, Kun Liu, Shuwen Liu, Fei Peng, Yingfeng Tu, and co-workers present facile hydrogen-powered microswimmers for precise and active hydrogen therapy towards acute ischemic stroke. [Extracted from the article]

The importance of mechanical signals in regulating the fate of macrophages is gaining increased attention recently. However, the recently used mechanical signals normally rely on the physical characteristics of matrix with non-specificity and instability or mechanical loading devices with uncontrollability and complexity. Herein, we demonstrate the successful fabrication of self-assembled microrobots (SMRs) based on magnetic nanoparticles as local mechanical signal generators for precise macrophage polarization. Under a rotating magnetic field (RMF), the propulsion of SMRs occurs due to the elastic deformation via magnetic force and hydrodynamics. SMRs perform wireless navigation toward the targeted macrophage in a controllable manner and subsequently rotate around the cell for mechanical signal generation. Macrophages are eventually polarized from M0 to anti-inflammatory related M2 phenotypes by blocking the Piezo1-activating protein-1 (AP-1）-CCL2 signaling pathway. The as-developed microrobot system provides a new platform of mechanical signal loading for macrophage polarization, which holds great potential for precise regulation of cell fate., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors. Exploration published by Henan University and John Wiley & Sons Australia, Ltd.)

Inspired by the tactic organisms in Nature that can self-direct their movement following environmental stimulus gradient, we proposed a DNase functionalized Janus nanoparticle (JNP) nanomotor system for the first time, which can be powered by ultralow nM to μM levels of DNA. The system exhibited interesting chemotactic behavior toward a DNA richer area, which is physiologically related with many diseases including tumors. In the presence of the subtle DNA gradient generated by apoptotic tumor cells, the cargo loaded nanomotors were able to sense the DNA signal released by the cells and demonstrate directional motion toward tumor cells. For our system, the subtle DNA gradient by a small amount (10 μL) of tumor cells is sufficient to induce the chemotaxis behavior of self-navigating and self-targeting ability of our nanomotor system, which promises to shed new light for tumor diagnosis and therapy.

Chemodynamic therapy (CDT) is an emerging strategy for cancer treatment based on Fenton chemistry, which can convert endogenous H 2 O 2 into toxic ·OH. However, the limited endocytosis of passive CDT nanoagents with low penetrating capability resulted in unsatisfactory anticancer efficacy. Herein, we propose the successful fabrication of a self-propelled biodegradable nanomotor system based on hollow MnO 2 nanoparticles with catalytic activity for active Fenton-like Mn 2+ delivery and enhanced CDT. Compared with the passive counterparts, the significantly improved penetration of nanomotors with enhanced diffusion is demonstrated in both the 2D cell culture system and 3D tumor multicellular spheroids. After the intracellular uptake of nanomotors, toxic Fenton-like Mn 2+ is massively produced by consuming overexpressed intracellular glutathione (GSH), which has a strong scavenging effect on ·OH, thereby leading to enhanced cancer CDT. The as-developed MnO 2 -based nanomotor system with enhanced penetration and endogenous GSH scavenging capability shows much promise as a potential platform for cancer treatment in the near future.

Inducing neural stem cells to differentiate and replace degenerated functional neurons represents the most promising approach for neural degenerative diseases including Parkinson's disease, Alzheimer's disease, etc. While diverse strategies have been proposed in recent years, most of these are hindered due to uncontrollable cell fate and device invasiveness. Here, we report a minimally invasive micromotor platform with biodegradable helical Spirulina plantensis ( S. platensis ) as the framework and superparamagnetic Fe 3 O 4 nanoparticles/piezoelectric BaTiO 3 nanoparticles as the built-in function units. With a low-strength rotational magnetic field, this integrated micromotor system can perform precise navigation in biofluid and achieve single-neural stem cell targeting. Remarkably, by tuning ultrasound intensity, thus the local electrical output by the motor, directed differentiation of the neural stem cell into astrocytes, functional neurons (dopamine neurons, cholinergic neurons), and oligodendrocytes, can be achieved. This micromotor platform can serve as a highly controllable wireless tool for bioelectronics and neuronal regenerative therapy.