Magnetically Driven Micro and Nanorobots

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(8), P. 4999 - 5041

Published: March 31, 2021

Manipulation and navigation of micro nanoswimmers in different fluid environments can be achieved by chemicals, external fields, or even motile cells. Many researchers have selected magnetic fields as the active actuation source based on advantageous features this strategy such remote spatiotemporal control, fuel-free, high degree reconfigurability, programmability, recyclability, versatility. This review introduces fundamental concepts advantages micro/nanorobots (termed here "MagRobots") well basic knowledge materials, setups for manipulation, field configurations, symmetry-breaking strategies effective movement. These are discussed to describe interactions between fields. Actuation mechanisms flagella-inspired MagRobots (i.e., corkscrew-like motion traveling-wave locomotion/ciliary stroke motion) surface walkers surface-assisted motion), applications other propulsion approaches, stimulation beyond provided followed fabrication techniques (quasi-)spherical, helical, flexible, wire-like, biohybrid MagRobots. Applications targeted drug/gene delivery, cell minimally invasive surgery, biopsy, biofilm disruption/eradication, imaging-guided delivery/therapy/surgery, pollution removal environmental remediation, (bio)sensing also reviewed. Finally, current challenges future perspectives development magnetically powered miniaturized motors discussed.

Language: Английский

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Layered double hydroxide-based nanomaterials for biomedical applications

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(14), P. 6126 - 6176

Published: Jan. 1, 2022

Against the backdrop of increased public health awareness, inorganic nanomaterials have been widely explored as promising nanoagents for various kinds biomedical applications. Layered double hydroxides (LDHs), with versatile physicochemical advantages including excellent biocompatibility, pH-sensitive biodegradability, highly tunable chemical composition and structure, ease composite formation other materials, shown great promise in In this review, we comprehensively summarize recent advances LDH-based Firstly, material categories are discussed. The preparation surface modification nanomaterials, pristine LDHs, nanocomposites LDH-derived then described. Thereafter, systematically describe potential LDHs applications drug/gene delivery, bioimaging diagnosis, cancer therapy, biosensing, tissue engineering, anti-bacteria. Finally, on basis current state art, conclude insights remaining challenges future prospects rapidly emerging field.

Language: Английский

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Environmentally Adaptive Shape-Morphing Microrobots for Localized Cancer Cell Treatment

ACS Nano, Journal Year: 2021, Volume and Issue: 15(11), P. 18048 - 18059

Published: Oct. 19, 2021

Microrobots have attracted considerable attention due to their extensive applications in microobject manipulation and targeted drug delivery. To realize more complex micro-/nanocargo (e.g., encapsulation release) biological applications, it is highly desirable endow microrobots with a shape-morphing adaptation dynamic environments. Here, environmentally adaptive (SMMRs) been developed by programmatically encoding different expansion rates pH-responsive hydrogel. Due combination magnetic propulsion, microcrab (SMMC) able perform microparticle delivery, including gripping, transporting, releasing "opening–closing" of claw. As proof-of-concept demonstration, microfish (SMMF) designed encapsulate (doxorubicin (DOX)) closing its mouth phosphate-buffered saline (PBS, pH ∼ 7.4) release the opening slightly acidic solution (pH < 7). Furthermore, localized HeLa cell treatment an artificial vascular network realized SMMF mouth. With continuous optimization size, motion control, imaging technology, these SMMRs will provide ideal platforms for microcargo operations on-demand release.

Language: Английский

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Synergistic Enhancement of Electrocatalytic Nitrogen Reduction Over Boron Nitride Quantum Dots Decorated Nb₂CT_x‐MXene

Small, Journal Year: 2021, Volume and Issue: 17(40)

Published: Sept. 9, 2021

Abstract Electrochemical N 2 fixation represents a promising strategy toward sustainable NH 3 synthesis, whereas the rational design of high‐performance catalysts for nitrogen reduction reaction (NRR) is urgently required but remains challenging. Herein, novel hexagonal BN quantum dots (BNQDs) decorated Nb CT x – MXene (BNQDs@Nb ) explored as an efficient NRR catalyst. BNQDs@Nb presents optimum activity with yield rate 66.3 µg h −1 mg (−0.4 V) and Faradaic efficiency 16.7% (−0.3 V), outperforming most state‐of‐the‐art catalysts, together excellent stability. Theoretical calculations revealed that synergistic interplay BNQDs enabled creation unique interfacial B sites serving catalytic centers capable enhancing activation, lowering energy barrier impeding H evolution.

Language: Английский

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Magnetic Microswarm Composed of Porous Nanocatalysts for Targeted Elimination of Biofilm Occlusion

ACS Nano, Journal Year: 2021, Volume and Issue: 15(3), P. 5056 - 5067

Published: Feb. 26, 2021

Biofilm is difficult to thoroughly cure with conventional antibiotics due the high mechanical stability and antimicrobial barrier resulting from extracellular polymeric substances. Encouraged by great potential of magnetic micro-/nanorobots in various fields their enhanced action swarm form, we designed a microswarm consisting porous Fe3O4 mesoparticles (p-Fe3O4 MPs) explored its application biofilm disruption. Here, p-Fe3O4 MPs swarm) was generated actuated simple rotating field, which exhibited capability remote actuation, cargo capacity, strong localized convections. Notably, could eliminate biofilms efficiency synergistic effects chemical physical processes: (i) generating bactericidal free radicals (•OH) for killing bacteria cells degrading MPs; (ii) physically disrupting promoting •OH penetration deep into motion. As demonstration targeted treatment, be clear along geometrical route on 2D surface sweep away clogs 3D U-shaped tube. This platform holds treating occlusions particularly inside tiny tortuous cavities medical industrial settings.

Language: Английский

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Magnetic Microswarm and Fluoroscopy‐Guided Platform for Biofilm Eradication in Biliary Stents

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(34)

Published: April 27, 2022

Biofilm eradication from medical implants is of fundamental importance, and the treatment biofilm-associated pathogen infections on inaccessible biliary stents remains challenging. Magnetically driven microrobots with controlled motility, accessibility to tiny lumen, swarm enhancement effects can physically disrupt deleterious biostructures while not developing drug resistance. Magnetic urchin-like capsule robots (MUCRs) loaded magnetic liquid metal droplets (MLMDs, antibacterial agents) are designed using natural sunflower pollen, therapeutic effect swarming MUCR@MLMDs explored for eradicating complex mixtures bacterial biofilm within collected patients. The external field triggers emergence microswarm induces MLMDs transform their shape into spheroids rods sharp edges. inherent microspikes MUCRs obtained edges actively rupture dense biological matrix multiple species embedded cells by exerting mechanical force, finally achieving synergistic eradication. precisely rapidly deployed stent via endoscopy in 10 min. Notably, fluoroscopy imaging used track navigate locomotion real-time. has great potential treating associated implants.

Language: Английский

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Control and Autonomy of Microrobots: Recent Progress and Perspective

Advanced Intelligent Systems, Journal Year: 2022, Volume and Issue: 4(5)

Published: April 3, 2022

After decades of development, microrobots have exhibited great application potential in the biomedical field, such as minimally invasive surgery, drug delivery, and bio‐sensing. Compared with conventional medical robotic systems, may be capable reaching more narrow vulnerable regions human body minimal damage. However, limited by small scale microrobots, microprocessors, power supplies, sensors can hardly integrated on‐board. Thus, new strategies for actuation feedback need to explored. Furthermore, open‐loop control method accomplished operators lack accuracy, long‐duration operation could bring a severe physical challenge many applications. Consequently, automatic aid theories is developed improve efficiency precision. To further promote automation level machine learning algorithms are expected provide solution let adapt dynamic environments undertake complex tasks. Herein, systematic introduction manipulation from closed‐loop given this review. It envisioned that will play an important role future

Language: Английский

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Controlled propulsion of micro/nanomotors: operational mechanisms, motion manipulation and potential biomedical applications

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(24), P. 10083 - 10119

Published: Jan. 1, 2022

Micro/nanomotors with advanced motion manipulation show great promise in biomedical fields. This review article critically summarizes the working principles, strategies, applications, and future prospects of micro/nanomotors.

Language: Английский

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Real-Time Ultrasound Doppler Tracking and Autonomous Navigation of a Miniature Helical Robot for Accelerating Thrombolysis in Dynamic Blood Flow

ACS Nano, Journal Year: 2022, Volume and Issue: 16(1), P. 604 - 616

Published: Jan. 4, 2022

Untethered small-scale robots offer great promise for medical applications in complex biological environments. However, challenges remain the control and imaging of a robot targeted delivery inside living body, especially flowing conditions (e.g., blood vessels). In this work, we report strategy to autonomously navigate miniature helical dynamic flow under ultrasound Doppler guidance. A magnetic torque force-hybrid approach is implemented, enabling actuation millimeter-scale against rotating field with controllable gradient. Experimental results demonstrate that (length 7.30 mm; diameter 2.15 mm) exhibits controlled navigation vascular environments, including upstream downstream pulsatile rates up 24 mL/min (mean velocity: 14.15 mm/s). During navigation, robot-induced signals enable real-time localization tracking Moreover, can be selectively navigated along different paths by actively controlling robot's orientation. We apply autonomous localizing thrombus accelerating thrombolysis rate. Compared conventional tissue plasminogen activator (tPA) thrombolysis, robot-enhanced shear stress tPA convection near clot-blood interface increase unblocking efficiency 4.8- 3.5-fold, respectively. Such imaging-guided provides simultaneous providing an intelligent toward diagnostic vivo.

Language: Английский

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Lighting up Micro-/Nanorobots with Fluorescence

Chemical Reviews, Journal Year: 2022, Volume and Issue: 123(7), P. 3944 - 3975

Published: Sept. 15, 2022

Micro-/nanorobots (MNRs) can be autonomously propelled on demand in complex biological environments and thus may bring revolutionary changes to biomedicines. Fluorescence has been widely used real-time imaging, chemo-/biosensing, photo-(chemo-) therapy. The integration of MNRs with fluorescence generates fluorescent unique advantages optical trackability, on-the-fly environmental sensitivity, targeting chemo-/photon-induced cytotoxicity. This review provides an up-to-date overview MNRs. After the highlighted elucidation about various propulsion mechanisms introductory information emphasis materials, we systematically illustrate design preparation strategies integrate substances their biomedical applications imaging-guided drug delivery, intelligent sensing In end, summarize main challenges provide outlook future directions work is expected attract inspire researchers from different communities advance creation practical application a broad horizon.

Language: Английский

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