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Fluid−fluid interfaces are an attractive platform for self-assembling nanoparticles into low-dimensional materials. In this Perspective, we review recent developments in the use of interfaces to direct the assembly of spherical and anisotropic nanoparticles into diverse and sophisticated architectures. We illustrate how nanoparticle clusters, strings, networks, superlattices, chiral lattices, and quasicrystals can be self-assembled by harnessing the frustration between interfacial and interparticle forces. We highlight the role of polymeric ligands attached to the surface of nanoparticles in modulating assembly behavior by directly altering particle−fluid and particle−particle interactions or by deforming at interfaces and junctions between particles. We conclude by providing a roadmap of key questions and opportunities in this exciting field of interfacial assembly.
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Anisotropic Particles through Multilayer Assembly
Abstract The anisotropy in the shape of polymeric particles has been demonstrated to have many advantages over spherical particulates, including bio‐mimetic behavior, shaped‐directed flow, deformation, surface adhesion, targeting, motion, and permeability. The layer‐by‐layer (LbL) assembly is uniquely suited for synthesizing anisotropic particles as this method allows for simple and versatile replication of diverse colloid geometries with precise control over their chemical and physical properties. This review highlights recent progress in anisotropic particles of micrometer and nanometer sizes produced by a templated multilayer assembly of synthetic and biological macromolecules. Synthetic approaches to produce capsules and hydrogels utilizing anisotropic templates such as biological, polymeric, bulk hydrogel, inorganic colloids, and metal–organic framework crystals as sacrificial templates are overviewed. Structure‐property relationships controlled by the anisotropy in particle shape and surface are discussed and compared with their spherical counterparts. Advances and challenges in controlling particle properties through varying shape anisotropy and surface asymmetry are outlined. The perspective applications of anisotropic colloids in biomedicine, including programmed behavior in the blood and tissues as artificial cells, nano‐motors/sensors, and intelligent drug carriers are also discussed.
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- Award ID(s):
- 1904816
- PAR ID:
- 10361624
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Bioscience
- Volume:
- 22
- Issue:
- 1
- ISSN:
- 1616-5187
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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