Article
Chemistry, Multidisciplinary
Yuchun He, Kai Yin, Lingxiao Wang, Tingni Wu, Qinwen Deng, Yapeng Dou, Christopher J. Arnusch
Summary: A magnetically actuated superhydrophilic robot sphere (MSR) based on femtosecond laser direct writing technology is developed for droplet steering. The MSR with uniform micro-/nanostructures on its surface can be remotely controlled to transport droplets using a contactless magnetic actuator. The method provides a novel and reliable approach for droplet manipulation and broadens its application.
Article
Chemistry, Analytical
Sumit Mohanty, Jiena Zhang, Jeffrey M. McNeill, Thom Kuenen, Frederic P. Linde, Jeroen Rouwkema, Sarthak Misra
Summary: This article introduces two bubble-powered micro-propeller designs that autonomously rotate under the excitation of sound waves, serving as both mobile microfluidic mixers and autonomous microrobots for targeted manipulation.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Multidisciplinary
Youngbin Lee, Florian Koehler, Tom Dillon, Gabriel Loke, Yoonho Kim, Juliette Marion, Marc-Joseph Antonini, Indie C. Garwood, Atharva Sahasrabudhe, Keisuke Nagao, Xuanhe Zhao, Yoel Fink, Ellen T. Roche, Polina Anikeeva
Summary: The widespread use of magnetic soft robots is hindered by complex control paradigms and challenges in fabricating devices across different scales. In this study, advancements in fiber-based actuators and magnetic elastomer composites are utilized to create 3D magnetic soft robots controlled by one-directional fields. These robots can crawl or walk in magnetic fields orthogonal to their motion plane. They can also act as cargo carriers and be simultaneously controlled in opposite directions using a single stationary electromagnet. This scalable fabrication and control approach opens up possibilities for future applications of magnetic soft robots in environments with constrained and complex fields.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Youngbin Lee, Florian Koehler, Tom Dillon, Gabriel Loke, Yoonho Kim, Juliette Marion, Marc-Joseph Antonini, Indie C. Garwood, Atharva Sahasrabudhe, Keisuke Nagao, Xuanhe Zhao, Yoel Fink, Ellen T. Roche, Polina Anikeeva
Summary: This study leverages advancements in magnetic materials and fiber-based actuators to create three-dimensional magnetic soft robots controlled by unidirectional fields. These robots demonstrate high programmability and scalability, allowing for cargo transportation and simultaneous control of multiple robots in specific environments.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jinsheng Zhao, Taiping Lu, Yixing Zhang, Chong Zhang, Chengfeng Pan, Yu Tan, Jiaqi Zhu, Bing Li, Li Zhang, Mingxing Shi, Xiangyu Li
Summary: This study proposes a design strategy for magnetically actuated adhesives that can switch between high and low levels of adhesion with a tuning ratio exceeding 50. By using non-contact magnetic field actuation, the adhesion interface can have interface cracks and generate a push force on the target object. Consequently, the pull-off force can be precisely adjusted according to the strength of the magnetic field. The adhesive also exhibits ultrafast detachment and shows advantages in transfer-print technology and on-demand detachment.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yicheng Ye, Hao Tian, Jiamiao Jiang, Weichang Huang, Ruotian Zhang, Huaan Li, Lu Liu, Junbin Gao, Haixin Tan, Meihuan Liu, Fei Peng, Yingfeng Tu
Summary: An efficient and dynamic antigen delivery system based on magnetically actuated OVA-CaCO3-SPIO robots (OCS-robots) is designed for active immunotherapy in this study. The OCS-robots demonstrate controllable motion capability under a rotating magnetic field, which enables acid-responsiveness, lysosome escape, and subsequent antigen cross-presentation by dendritic cells. The dynamic OCS-robots promote the crosstalk between dendritic cells and antigens, leading to significant tumor immunotherapy effects on melanoma through cytotoxic T lymphocytes (CTLs).
Article
Engineering, Electrical & Electronic
Bradley J. Nelson, Simone Gervasoni, Philip W. Y. Chiu, Li Zhang, Ajmal Zemmar
Summary: This article focuses on the state-of-the-art and future directions for magnetically actuated medical robots within the human body. It discusses magnetically guided tethered probes, untethered devices (microrobots and nanorobots), and magnetic navigation systems that have been or could be utilized to provide increased control and safety for physicians and patients.
PROCEEDINGS OF THE IEEE
(2022)
Article
Chemistry, Multidisciplinary
Ying Zheng, Guizhou Zheng, Yuan Yuan Li, Xia Gong, Zhipeng Chen, Linyu Zhu, Yunsheng Xu, Xi Xie, Shuo Wu, Lelun Jiang
Summary: An implantable magnetically-actuated capsule (IMAC) and its portable magnetic actuator (MA) have been developed for on-demand and robust drug delivery. The IMAC utilizes magnetic balls to trigger drug release under a strong magnetic field, ensuring precise and reproducible drug delivery. The IMAC can navigate to lesion sites and release drugs in a controlled manner using magnetic fields.
JOURNAL OF CONTROLLED RELEASE
(2023)
Review
Computer Science, Information Systems
Weiyuan Chen, Jianbo Sui, Chengyong Wang
Summary: Capsule endoscopy is a non-invasive procedure that uses a wireless camera inside a capsule to capture images of the gastrointestinal tract. However, the current capsule endoscope has limitations in controllable locomotion and lacks extended functions. Magnetic actuation offers a solution to expand the capabilities of capsule endoscopy and develop multifunctional capsule robots.
Article
Chemistry, Multidisciplinary
Changhee Son, Zhengyu Yang, Seungbeom Kim, Placid M. Ferreira, Jie Feng, Seok Kim
Summary: This study introduces a bidirectional droplet manipulation method on a magnetically actuated superhydrophobic ratchet surface. Computational models were developed to predict the manipulation effect, which was confirmed by experimental results. The findings provide substantial insights into the design and optimization of magnetically actuated superhydrophobic ratchet surfaces for droplet manipulation in digital microfluidic applications.
Article
Chemistry, Multidisciplinary
Lu Liu, Juanyan Wu, Bin Chen, Junbin Gao, Ting Li, Yicheng Ye, Hao Tian, Shuanghu Wang, Fei Wang, Jiamiao Jiang, Juanfeng Ou, Fei Tong, Fei Peng, Yingfeng Tu
Summary: This study demonstrates the wireless and precise activation of muscle using magnetic biohybrid microswimmers combined with near-infrared laser irradiation. The photothermal effect of the incorporated nanoparticles can efficiently trigger muscle contraction. This method is of great significance for tissue engineering and bionics.
Article
Biophysics
Alessandro Falconieri, Nikita Taparia, Sara De Vincentiis, Valentina Cappello, Nathan J. Sniadecki, Vittoria Raffa
Summary: New strategies to promote neuronal regeneration should focus on increasing the speed of axonal elongation. Mechanical force, through a process called stretch growth, has been found to significantly influence the elongation rate, in addition to biochemical signaling. In this study, the application of magnetic microposts to primary hippocampal neurons led to an increase in axon length, along with an increase in microtubule density and endoplasmic reticulum mass, indicating stretch growth. These findings suggest that magnetically-actuated microposts can accelerate axon growth, opening up possibilities for future applications in neuronal regeneration.
BIOPHYSICAL JOURNAL
(2022)
Article
Immunology
Chirag Sachar, Lance C. Kam
Summary: This study introduces a method to change the structural rigidity of microscale elastomer pillars using magnetic fields, showing that an increase in pillar spring constant alters the morphology of T cells and IL-2 secretion. This approach separates local substrate stiffness from long-range structural rigidity, revealing new insights into T cell interaction with their environment.
FRONTIERS IN IMMUNOLOGY
(2021)
Article
Chemistry, Analytical
Pascal M. Weber, Ulrike Wallrabe, Matthias C. Wapler
Summary: We present a method for self-sensing a magnetically actuated prism, eliminating the need for additional sensors in a feedback loop. By determining the optimal measurement frequency and developing a combined actuation and measurement driver, we demonstrate accurate measurement of the prism's tilt angle with an accuracy of +/-0.1 degrees in the polar angle and +/-20 mrad in the azimuthal angle.
Article
Materials Science, Multidisciplinary
Jingze Xue, Zhuangzhuang Tian, Jinghao Tang, Xinze Xiao, Chuankai Du, Yan Liu
Summary: Inspired by molluscs, researchers have developed a multi-locomotion soft robot based on magnetic composites. The robot generates time-varying shapes using a space variable magnetic field and achieves customized crawling maneuvers and path planning through control strategies.
MATERIALS & DESIGN
(2023)
Article
Physics, Multidisciplinary
Carolina Rodriguez-Gallo, Antonio Ortiz-Ambriz, Pietro Tierno
Summary: The study demonstrated that boundaries can be engineered to control the bulk behavior in a colloidal artificial ice, with an antiferromagnetic boundary forcing the system to rapidly reach the ground state, and strategically placed defects at corners generating novel bistable states or topological strings. This approach could be extended to other frustrated micro- and nanostructures where boundary conditions can be engineered using lithographic techniques.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Pietro Tierno, Alexey Snezhko
Summary: This minireview discusses recent advancements in surface magnetic rotors, which can be remotely spun, steered, interaction-tuned, and assembled using external magnetic modulations. These microscopic wheels have potential applications in microfluidic devices, drug delivery, mixing, and as model systems for biological active matter research. Optically monitoring these dissipative colloidal systems can reveal complex collective phenomena under the influence of external fields.
Article
Physics, Multidisciplinary
Berta Martinez-Prat, Ricard Alert, Fanlong Meng, Jordi Ignes-Mullol, Jean-Francois Joanny, Jaume Casademunt, Ramin Golestanian, Francesc Sagues
Summary: Experimental results of active nematic fluid show that kinetic energy spectrum follows theoretical predictions at small and intermediate scales, but is influenced by the 3D oil layer at larger scales, leading to the emergence of a new scaling regime. The study reveals that external dissipation plays a significant role in affecting the spectrum properties.
Article
Physics, Applied
Raul Josue Hernandez-Hernandez, Thomas M. Fischer, Pietro Tierno
Summary: This study investigates the pair interactions between magnetically driven colloidal microrotors with an anisotropic shape. The particles interact through dipolar forces and hydrodynamic interactions (HIs) when they approach each other. When the magnetic field is close to a specific angle, dipolar interactions vanish and the pair's dynamics are solely driven by HIs. A theoretical description is provided to understand the role of anisotropy on the collective dynamics.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Sergi G. Leyva, Ralph L. Stoop, Ignacio Pagonabarraga, Pietro Tierno
Summary: In this study, we demonstrate the significant impact of the dispersing medium on the collective dynamics of interacting Brownian particles in a ratchet transport system. The long-range hydrodynamic interactions (His) result in a speed-up effect, leading to a higher translational speed and the formation and growth of clusters perpendicular to the driving direction. This research sheds light on the role of the dispersing medium in the dynamics of driven colloidal matter and the morphology of clusters.
Article
Chemistry, Multidisciplinary
Gaspard Junot, Sergi G. Leyva, Christoph Pauer, Carles Calero, Ignacio Pagonabarraga, Tim Liedl, Joe Tavacoli, Pietro Tierno
Summary: In this study, we demonstrate the transport of lithographically shaped magnetic microtriangles in viscous fluids using a precessing magnetic field. The microtriangles undergo complex transport modes, including a surfing-like drift and a transversal drift, which is generated by the asymmetric shape of the triangles. We explain this phenomenon with a minimal numerical model and suggest that this method can be extended to other anisotropic-shaped magnetic materials.
Article
Chemistry, Multidisciplinary
Gaspard Junot, Carles Calero, Jose Garcia-Torres, Ignacio Pagonabarraga, Pietro Tierno
Summary: Magnetic nanorods in water can be controlled in any direction and generate strong hydrodynamic flow fields using rotating fields. As the frequency of the rotating field increases, these nanopropellers undergo a transition from rolling to kayak-like motion due to increased viscous drag. A theoretical model explains these observations and quantifies the trapping and expelling of microscopic cargoes, while numerical simulations reveal the generated hydrodynamic flow field. These propulsion regimes have practical applications in microfluidic devices for precise sorting of microscopic cargoes.
Article
Physics, Applied
Guillermo Camacho, Alejandro Rodriguez-Barroso, Oscar Martinez-Cano, Jose R. Morillas, Pietro Tierno, Juan de Vicente
Summary: Shear thinning fluids show a decrease in viscosity with increasing shear rate. We experimentally demonstrate a deterministic ratchet effect in such fluids for directed transport of microscopic particles under a square-wave magnetic force. The shear thinning nature of the medium raises the mean speed for strong forces, breaking the spatial symmetry of particle displacement and generating net colloidal transport.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
Carolina Rodriguez-Gallo, Antonio Ortiz-Ambriz, Cristiano Nisoli, Pietro Tierno
Summary: Controlling the ice rule through geometry transformations, the topological properties of colloidal ice are studied. It is found that a geometric transformation from Shakti to Cairo leads to a breakdown of the ice rule, and a transfer of topological charge among sublattices is observed, which can be controlled in sign and intensity.
COMMUNICATIONS PHYSICS
(2023)
Article
Physics, Multidisciplinary
Carolina Rodriguez-Gallo, Antonio Ortiz-Ambriz, Cristiano Nisoli, Pietro Tierno
Summary: In this study, we investigate the low energy states and the emergence of topological defects in an artificial colloidal ice in the Cairo geometry using experiments and numerical simulations. By increasing the interaction strength, positive charges accumulate at the z = 4 vertices and are screened by negative charges at the z = 3 vertices, resulting in a strongly coupled disordered state. Furthermore, analyzing the mean chirality associated with each pentagonal plaquette reveals that the disordered ensemble in this geometry is massively degenerate and corresponds to a frustrated antiferrotoroid structure.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
Gaspard Junot, Marco De Corato, Pietro Tierno
Summary: We observe the emergence of large zigzag bands in a population of actuated magnetic rotors, which behave as active shakers. By combining experimental analysis with simulations, we show that the special flow field created by the shakers is the key ingredient for the observed spatiotemporal pattern.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Dominik Lips, Eric Cereceda-Lopez, Antonio Ortiz-Ambriz, Pietro Tierno, Artem Ryabov, Philipp Maass
Summary: The study investigates the collective transport properties of colloidal particles in a rotating ring of optical traps. It is found that the particles are driven by a vortex flow of the surrounding fluid in the corotating reference frame. The jamming behavior observed with increasing particle density is attributed to enhanced energetic barriers between the optical traps due to hydrodynamic interactions. The study highlights the importance of considering the driving mechanism and hydrodynamic interactions in soft matter and biological systems.
Article
Chemistry, Physical
Joan Codina, Helena Massana-Cid, Pietro Tierno, Ignacio Pagonabarraga
Summary: Investigated the directed motion in clusters composed of passive and catalytically active particles and explained the reversal in transport direction using a theoretical model. Further built complex architectures capable of rapid assembly and disassembly under light control.
Article
Chemistry, Physical
Gaspard Junot, Xuefeng Wei, Jordi Ortin, Ramin Golestanian, Yanting Wang, Pietro Tierno, Fanlong Meng
Summary: This article investigates how soft gels mediate the organization of embedded magnetic microparticles when driven by an external field. By constructing a continuum theory and conducting experiments, the delicate balance between magnetic dipole-dipole interactions, thermal fluctuations, and elasticity of the polymer network is verified to influence the collective dynamics of the embedded particles. The proposed model has implications for technological advancements in multifunctional hydrogel materials.
Article
Physics, Multidisciplinary
Helena Massana-Cid, Demian Levis, Raul Josue Hernandez Hernandez, Ignacio Pagonabarraga, Pietro Tierno
Summary: This study investigates phase separation in a chiral fluid composed of spinning ferromagnetic colloids. The research shows that hydrodynamics dominate over attractive magnetic interactions at high spinning frequencies, leading to the assembly of controllable-size rotating clusters. The results highlight the role of fluid-mediated long-range interactions in controlling coarsening and dynamic self-assembly in chiral active systems.
PHYSICAL REVIEW RESEARCH
(2021)
