Self‐Assembled Artificial Nanocilia Actuators

Abstract

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202200185. Here, a programmable self-assembly strategy is presented that can direct magnetic NPs into a highly ordered responsive artificial nanocilia actuator with exquisite nanometer 3D structural arrangements. The self-assembled artificial NP cilia can maintain their structural integrity through the interplay of interparticle interactions. Interestingly, the nanocilia can exhibit a fieldresponsive actuation motion through "rolling and sliding" between assembled NPs rather than bending the entire ciliary beam. It is demonstrated that oleic acid coated over the NPs acts as a lubricating bearing and enables the rolling/sliding-based actuation of the cilia.

3D Printable Self-Adhesive and Self-Healing Ionotronic Hydrogels for Wearable Healthcare Devices

“…The PPT hydrogels have relatively low conductivity (∼5 mS m –1 ) but showed a wide working range of up to 2000% strain. The conductivity of the PPT hydrogels can be improved by utilizing additional conductive filler materials such as carbon nanotubes, graphene oxides, or metallic nanowires, which will be our future work. ,, Nonetheless, we believe that ionotronic PPT hydrogels with self-adhesion, self-healing, 3D printability, and conductivity can be employed in a wide range of applications, including wearable healthcare devices, − energy storage devices, , structural health monitoring, and soft robotics. ,, In particular, the wide sensing range of PPT hydrogels is expected to be highly useful not only for monitoring human motion but also for application to emerging soft robots with high actuation ranges of hundreds of % or more. , …”

“…6,50,51 Nonetheless, we believe that ionotronic PPT hydrogels with self-adhesion, self-healing, 3D printability, and conductivity can be employed in a wide range of applications, including wearable healthcare devices, 52−54 energy storage devices, 8,55 structural health monitoring, 56 and soft robotics. 7,57,58 In particular, the wide sensing range of PPT hydrogels is expected to be highly useful not only for monitoring human motion but also for application to emerging soft robots with high actuation ranges of hundreds of % or more. 59,60 ■ ASSOCIATED CONTENT * sı Supporting Information…”

Recent Progress on the Development of Magnetically‐Responsive Micropillars: Actuation, Fabrication, and Applications

“…In addition to the growth of the magnetic micropillars from the bottom to the top, an aerosol sprinkle technique can stack Fe 3 O 4 nanoparticles one by one to form magnetic micropillars, as shown in Figure 5E. [110] After the mixture with monodispersed nanoparticles was sprayed out of the nozzle, the magnetic nanoparticles were converted into the vapor state and fell over a Si substrate with patterned nickel islands. The nickel sites concentrated and intensified the external magnetic field such that the magnetic nanoparticles were attracted and positioned on the nickel islands.…”

Magnetoresponsive Artificial Cilia Self-Assembled with Magnetic Micro/Nanoparticles

“…Indeed, previous studies have successfully constructed a linear chain of magnetic particles using patterned magnetic fields. , However, they were mostly planar 2D structures or exhibited limited ARs . To overcome the aforementioned limitations, our group recently proposed a 3D self-assembly technique that can direct magnetic NPs into an isolated vertical nanocilia array with nanoscale diameters, high ARs, and controllable pitches utilizing patterned magnetic fields and vapor-phase magnetite (Fe 3 O 4 ) NPs . However, the resulting cilia had only nanometer diameters (130–373 nm) and limited absolute heights (373 nm–10 μm), as only nanometer particles (diameters: 130–373 nm) were used in our previous study.…”

“…35 To overcome the aforementioned limitations, our group recently proposed a 3D self-assembly technique that can direct magnetic NPs into an isolated vertical nanocilia array with nanoscale diameters, high ARs, and controllable pitches utilizing patterned magnetic fields and vapor-phase magnetite (Fe 3 O 4 ) NPs. 36 However, the resulting cilia had only nanometer diameters (130−373 nm) and limited absolute heights (373 nm−10 μm), as only nanometer particles (diameters: 130−373 nm) were used in our previous study. In contrast, biological cilia have a wider range of sizes.…”