Magnetically Actuated Cell‐Robot System: Precise Control, Manipulation, and Multimode Conversion

Abstract

with efficient locomotion in fluids. Particularly, in fields that require biosafety, these robots need to be biofriendly, biocompatible, and multifunctional. In recent years, cell membrane-coated microrobots were designed, which provided new possibilities for researchers to easily harness native biological functions. [10,11] Additionally, biological template-based microrobots, such as bacterium-based robots, [12,13] sperm-based robots, [14] and cell-based motors, [15,16] have extraordinary properties while maintaining their original functionality. By providing these biological robots with new characteristics, they can be propelled by an external field to achieve various functions. For example, researchers have created cell-based delivery systems with the property of low toxicity and immunogenicity including the red blood cells, [17] platelets, [18] stem cells, [19] immune cells, [20] and tumor cells [21] that could be controlled to achieve precise site-specific delivery with better treatment efficacy. [22,23] Recently, magnetically propelled microrobots have gained particular attention in the bioengineering field, since magnetic fields are capable of penetrating most materials with minimal interaction and are nearly harmless. [24][25][26][27][28][29] Inspiringly, these magnetically actuated robots demonstrate flexible controllability to navigate mazes and could be used to manipulate cells precisely. [30,31] Exposed to a magnetic field, different magneticdriven microrobots can be controlled simultaneously and wirelessly with high precision. Therefore, microrobotic swarm behavior emerges when a large number of magnetic robots are activated by an external field. Although a single microrobot can achieve complex tasks, the power of an individual is always limited. In nature, swarm behavior appears everywhere. Specifically, bees collaborate to work efficiently, ant colonies work together to carry larger objects, and a school of fish swim together to resist predators. In the microworld, a magnetically driven robot swarm is promising because the swarm has a flexible morphology, [32] can travel through narrow channels, [33,34] and can even be observed in real organisms. [35] However, the implementation of biocompatible and biofriendly robot swarms is still a challenge.Immune cells are widely known as excellent carriers for targeted drug delivery, [36][37][38][39][40] owing to their capability to be decorated with functional nanoparticles. For robotics and cell manipulation, using a single cell robot to manipulate other Border-nearing microrobots with self-propelling and navigating capabilities have promising applications in micromanipulation and bioengineering, because they can stimulate the surrounding fluid flow for object transportation. However, ensuring the biosafety of microrobots is a concurrent challenge in bioengineering applications. Here, macrophage template-based microrobots (cell robots) that can be controlled individually or in chain-like swarms are proposed, which can transport various objects. The cell rob...

Cell‐Based Micro/Nano‐Robots for Biomedical Applications: A Review

“…Versatile robots have been fabricated and propelled using magnetic fields. [ 92,93 ] Magnetically controlled micro/nano‐robots based on cells, [ 42,94 ] bacteria, [ 95,96 ] algae, [ 97,98 ] sperms, [ 79 ] and other biotemplates have broadened the fabrication of conventional 3D‐printed micro/nano‐robots. [ 99,100 ]…”

“…Versatile robots have been fabricated and propelled using magnetic fields. [92,93] Magnetically controlled micro/nano-robots based on cells, [42,94] bacteria, [95,96] algae, [97,98] sperms, [79] and other biotemplates have broadened the fabrication of conventional 3D-printed micro/nano-robots. [99,100] In permanent magnet drive systems, the magnetic field is generated by a permanent magnet and controlled by adjusting the position of the permanent magnet.…”

Biohybrid Microswimmers for Antibiotic Drug Delivery Based on a Thiol‐Sensitive Release Platform

“…Among the latter, microswimmers are of great interest due to their potential to mask and carry active drugs and direct those towards the specific target site in a complex environment [18,19] . Both chemical and biological microswimmers have been explored for such tasks, with the latter being evolutionarily optimized to survive and perform in complex biological environments [20–51] . Chlamydomonas reinhardtii microalgae are generally recognized as safe (GRAS), biodegradable, and are not considered to trigger the immune response of the human body [52] .…”

Spatiotemporally Actuated Hydrogel by Magnetic Swarm Nanorobotics

“…At the same time, micro/nanorobots as a whole can enhance the ability to perform delivery tasks, such as transporting and manipulating large cargoes. , Flexible shape shifts also make them more adaptable to complex environments to reach their targets at high speeds . These miniature nanorobot populations offer great potential in biomedical applications, such as biocatalysis, , in vivo imaging, − and micromanipulation, − and have become the most active research area in recent years, especially in targeted delivery. − …”