Wenjun Chen

Periodontitis necessitates targeted therapy due to its high prevalence, progressive tissue destruction, and systemic disease links. Conventional mechanical debridement and pharmacological treatments are limited by complex periodontal barriers, including viscous crevicular fluid and resilient biofilms, which impede bacterial eradication and drug delivery. Here, we engineered magnetically actuated microrobots with gold nanothorns for disrupting biofilms and penetrating mucus barriers. Fabricated by encapsulating curcumin in antibacterial ionogel microspheres with asymmetric magnetic deposition and nanothorn functionalization, these microrobots enabled precise magnetic navigation in viscous media, while penetrating a biomimetic mucus analog, enhancing periodontal retention, and mechanically dislodging biofilms. Furthermore, ethanol-responsive release of curcumin enhanced its bioavailability, thereby scavenging free radicals and modulating macrophage phenotypes to alleviate inflammation. Guided by a toothbrushing-inspired handheld magnetic controller, microrobots evaluated using in vivo murine models demonstrated reduced inflammation, inhibited bone resorption, improved tissue health, and oral microbiota remodeling toward ecological balance, showing promise for targeted periodontitis therapy.

Endometrial cancer, accounting for over 90% of uterine malignancies, has experienced a significant global rise in incidence and mortality. Conventional therapies face limitations including fertility compromise, systemic toxicity, drug resistance, and poor outcomes in advanced/recurrent cases. Considering the unique physical and chemical properties of nanomaterials, the emerging drug delivery approaches based on nanomaterials are regarded as a promising pathway for enhanced therapeutic efficiency to combat endometrial cancer. Herein, this mini-review discusses emerging drug delivery approaches to overcome current treatment challenges. We classify common therapeutic nanomaterials into polymer-based nanocarriers, quantum dots, liposomes, and exosomes, analyzing their synthesis, mechanisms, and preclinical efficacy. Finally, scientific challenges and future perspectives for ongoing research in this field are presented.

In recent years, extensive strategies are developed for designing and manufacturing micro‐ and nanomotors. However, the controlled assembly and motion modulation of self‐assembled micromotors via directional interactions remain challenging. While host–guest systems, particularly azobenzene‐β‐cyclodextrin (Azo‐β‐CD) interactions, are well‐established in supramolecular chemistry, their application to structurally guided micromotor assembly and motion control is underexplored. Here, this host–guest chemistry is integrated with established catalytic (Pt/H ₂ O ₂ ) and magnetic actuation mechanisms to achieve programmable assembly of micromotors with defined architectures. By using Azo‐ and β‐CD‐modified microspheres as host and guest components separately, spatially controlled assembly is demonstrated into structured motors. The motors have dual‐mode propulsion: chemically driven motion via Pt‐catalyzed decomposition of 10 wt.% H ₂ O ₂ and magnetic field‐directed locomotion. This synergy of supramolecular assembly and established actuation mechanisms advances structural precision in micromotor design, offering a platform for multifunctional systems. The findings bridge supramolecular chemistry and microengineering, providing a framework for applications requiring tailored architectures and multimodal motion, such as targeted drug delivery or environmental sensing.

Enzyme-catalyzed micro/nanomotors (MNMs) exhibit tremendous potential for biological isolation and sensing, because of their biocompatibility, versatility, and ready access to biofuel. However, flow field generated by enzyme-catalyzed reactions might significantly hinder performance of surface-linked functional moieties, e.g., the binding interaction between MNMs and target cargos. Herein, we develop enzymatic micromotors with spatially selective distribution of urease to enable the independent operation of various modules and facilitate the capture and sensing of exosomes. When urease is modified into the motors' cavity, the flow field from enzyme catalysis has little effect on the exterior surface of the motors. The active motion and encapsulating urease internally result in enhancement of ∼35% and 18% in binding efficiency of target cargos, e.g., exosomes as an example here, compared to their static counterparts and moving micromotors with urease modified externally, respectively. Once exosomes are trapped, they can be transferred to a clean environment by the motors for Raman signal detection and/or identification using the surface Raman enhancement scattering (SERS) effect of coated gold nanoshell. The biocatalytic micromotors, achieving spatial separation between driving module and function module, offer considerable promise for future design of multifunctional MNMs in biomedicine and diagnostics.

Hydrogel, a material with outstanding biocompatibility and shape deformation ability, has recently become a hot topic for researchers studying innovative functional materials due to the growth of new biomedicine. Due to their stimulus responsiveness to external environments, hydrogels have progressively evolved into “smart” responsive (such as to pH, light, electricity, magnetism, temperature, and humidity) materials in recent years. The physical and chemical properties of hydrogels have been used to construct hydrogel micro-nano robots which have demonstrated significant promise for biomedical applications. The different responsive deformation mechanisms in hydrogels are initially discussed in this study; after which, a number of preparation techniques and a variety of structural designs are introduced. This study also highlights the most recent developments in hydrogel micro-nano robots’ biological applications, such as drug delivery, stem cell treatment, and cargo manipulation. On the basis of the hydrogel micro-nano robots’ current state of development, current difficulties and potential future growth paths are identified.

Oral drug delivery is a common route for management of inflammatory bowel disease (IBD) but suffers from low bioavailability and systemic side effects during passage through the alimentary canal. Here, we present a therapeutic nano reagent of a ferulic acid-derived lignin nanoparticle (FALNP). We showed that FALNP with favorable antioxidant activity can regulate IBD. More importantly, the intestinal pH-responsive degradability of FALNP allows it to withstand the harsh gastric acid environment, bypass physiological barriers, and target the intestine for gastrointestinal delivery. In vivo experiments showed that oral administration of FALNP markedly relieved pathological symptoms in a mouse model of acute colitis by reducing oxidative stress and regulating the gut microbiome. By integrating anti-inflammatory medicine, FALNP also can be used as a bioactive carrier to exert a potent synergistic therapeutic effect. In addition to colitis, FALNP can be readily adaptable for use as a carrier platform for therapy of many other intestinal diseases.

Miniaturization of synthetic micro/nanomotors (MNMs) brings great application prospects but limits their functionalization ability. Here, we report self-fueled metal organic framework (MOF) micromotors that are endowed with capabilities of self-propulsion and antibacterial therapy by their material's intrinsic properties. The spontaneous degradation of the MOF micromotors in water would release their own constituting components of ions which act as fuels to propel themselves by ionic diffusionphoresis with a high energy conversion efficiency. Meanwhile, the metal cations released from the MOF micromotors can also serve as antibacterial reagents to kill Escherichia coli (E. coli) with motion enhanced efficacy, which could significantly accelerate the wound closure in a bacterially infected wound model in vivo. Our work provides a general guidance for constructing functional MNMs by taking advantage of the motors' own materials to achieve self-propulsion and on-demand task assignments, which would promote future development of highly integrated micro/nanorobotic systems at micro/nanoscale.

Achieving molecular sample capture at micro/nanoscales while integrating functions of controllable loading and real-time monitoring of cargo molecules is of great significance in the development of intelligent micro/nanorobots. Herein, we prepare a temperature-responsive microsampling nanorobot by encapsulating metal (Au) nanodots inside hollow mesoporous silica nanoparticles and grafting a temperature-responsive polymer, poly(N-isopropylacrylamide), on their external surface. The molecular gate of nanochannels accessing the internal hollow reservoir can be switched between "open" and "closed" states by regulating the temperature, allowing on-demand loading and releasing of small molecules. The internally embedded surface-enhanced Raman scattering hotspots of gold nanodots can serve as sensing probes for real-time detection of the molecular cargo load inside the hollow nanorobots. Furthermore, we demonstrate temperature-dependent self-propulsion behavior of the nanorobots driven by enzymatic reactions. The active motion behavior can favorably regulate the loading efficiency of molecular cargos. In addition, by further introducing the magnetic component Ni, the nanorobots can accomplish effective transportation of cargo molecules by magnetic guidance under real-time Raman monitoring. The current strategy is expected to provide a manipulable nanorobot platform for precise biomedical sampling, which holds promising potential for disease diagnosis or controlled drug delivery in precision medicine.