Micro/nanorobots have been extensively investigated for biomedical applications due to their efficiency in targeted therapy and accuracy in local diagnostics. Magnetic micro/nanorobots are viewed as fuel-free tools with non-destructive penetrating capabilities through biological tissues, as magnetic fields can control the movement of micro/nanorobots within biological systems.
study: Magnetic Micro/Nanorobots: A New Era in BiomedicineImage Credit: Corona Borealis Studio/Shutterstock.com
In addition to micro/nanorobot integration, remote control and imaging are essential to that end. in vivo biomedical applications.Articles published in Advanced intelligent system We described the fabrication method and driving mechanism of micro/nanorobots controlled by magnetic fields.
In addition, this review highlights the application of magnetic micro/nanorobots as carriers of drugs, living cells and biological agents, as well as surgical tools for sample collection, biofilm degradation, and ophthalmic surgery.
Micro/nano robots and their driving force
In recent years, micro/nano robots have progressed rapidly. Most existing micro/nanorobots execute commands via externally controlled self-propelled mechanisms. Unlike large micro/nanorobots that move by inertia, their smaller counterparts that move in environments with low Reynolds number fluids need to be continuously powered.
Such environments are dominated by viscous forces, but inertial forces are negligible. Therefore the object moves slowly. However, due to their small size, it is difficult to put engines and batteries into micro/nano robots. As a result, researchers have focused on the propulsion of micro/nanorobots.
Micro/nanorobots are classified as magnetically driven, chemically driven, ultrasonically driven, optically driven, or electrically driven, depending on the power source used. Chemically powered micro/nano robots move faster than otherwise powered ones. However, it has no direction. Additionally, chemical fuels such as hydrogen peroxide, hydrazine, sodium hydroxide, and hydrochloric acid are toxic.
Light-driven micro/nanorobots require high-intensity light sources and hydrogen peroxide, which can affect biocompatibility. Ultrasound-driven micro/nanorobots are biocompatible, but their orientation is difficult to control. Electric micro/nanorobots hold great promise for fuelless transportation. However, their biological applications are limited and poorly documented.
Biomedical applications of micro/nano robots
Accurate and efficient delivery of therapeutic agents to target sites, especially hidden and hard-to-reach locations in the body, is a significant challenge for passive drug delivery systems. This problem can be solved using active and intelligent drug delivery systems consisting of micro/nanorobots propelled by external magnetic fields.
Micro/nanorobots can carry a variety of cargoes, including pharmaceuticals, biologics, living cells, and inorganic therapeutics. The carrier can be driven to a specific location by a magnetic field, and the loaded therapeutic agent can be released by changing the environment or applying an external magnetic field. A simple and universal method was reported for manipulating droplets using a magnetically driven robot.
The inability of various medical tools to penetrate deep tissue limits micrometric or nanoscale surgery. Due to their small size, micro/nano robots can access areas inaccessible to blades and catheters. In addition, it reduces the risk of infection while improving recovery time, surgical accuracy and control.
Magnetic nanorobots, composed of carbon nanocoils guided by a rotating electromagnetic field, can precisely localize individual cells and penetrate cell membranes. Surface-enhanced Raman scattering biosensing signals from plasma and nuclei of cells were collected using externally deposited gold nanofilms. This magnetic nanorobot has broad applications as an integrated therapeutic platform for precision medicine.
Future Prospects of Micro/Nano Robots
I need a new preparation method in vivo Biomedical applications of micro/nanorobotics to optimize and functionalize structures and achieve cost-effective large-scale preparation of various systems.
Micro/nanorobotic materials must meet criteria for practical biomedical and environmental applications, improve biodegradability and biocompatibility, and reduce toxicity in medical and biological settings.
Swarm or collective robot behavior can effectively perform tasks in complex biological environments that individual micro/nano robots cannot achieve, and improve work efficiency by utilizing biological imaging techniques. increase. Micro/nanorobots have a long way to go before they are used on a large scale in clinical settings, but their use in precision medicine remains important.
Conclusion
In summary, there have been significant advances in the design and fabrication of micro/nanorobots with various capabilities over the past decade. These artificial micro/nanorobots can transport drugs, bioagents and living cells in living systems.Also surgical tools for ophthalmic surgery, sample collection, and biofilm degradation, and in vitro When in vivo Imaging using light, sound, magnetic fields, etc.
Additional research on designing robots with high efficiency, low cost, scalability, and environmentally friendly microfabrication techniques is required to enhance micro/nanorobots in biomedical applications.
reference
Liu D. others(2022), Magnetic Micro/Nanorobots: A New Age in Biomedicines. Advanced intelligent system. https://doi.org/10.1002/aisy.202200208
