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Programmable self-assembly of smart, digital, and structurally complex materials from simple components at size scales from the macro to the nano remains a long-standing goal of material science. Here, we introduce a platform based on magnetic encoding of information to drive programmable self-assembly that works across length scales. Our building blocks consist of panels with different patterns of magnetic dipoles that are capable of specific binding. Because the ratios of the different panel-binding energies are scale-invariant, this approach can, in principle, be applied down to the nanometer scale. Using a centimeter-sized version of these panels, we demonstrate 3 canonical hallmarks of assembly: controlled polymerization of individual building blocks; assembly of 1-dimensional strands made of panels connected by elastic backbones into secondary structures; and hierarchical assembly of 2-dimensional nets into 3-dimensional objects. We envision that magnetic encoding of assembly instructions into primary structures of panels, strands, and nets will lead to the formation of secondary and even tertiary structures that transmit information, act as mechanical elements, or function as machines on scales ranging from the nano to the macro.
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Selective Manipulation and Trapping of Magnetically Barcoded Materials
Abstract Manipulation of magnetic materials (including remote‐controlled motions or structural deformations) plays a major role in modern micro‐ to macro‐scale systems. Magnetic operations create highly predicable outcomes in the behavior of systems, however these have difficulty performing subordinate and/or higher‐order operations. This lack of selectivity remains a critical drawback of magnetic manipulation schemes. Here, a strategy of engineering highly selective magnetic responses is studied and implemented. This is achieved by combining magnetic barcodes (“keys” encoded with layers of magnetic anisotropy) with programmable magnetic platforms (locking select codes in place with matching spatiotemporal magnetic fields). Presently, barcodes are realized by encoding hydrogel with sequences of magnetic microchains with binary spatial orientations. A number of unique capabilities of this approach are studied, including the untethered, selective anchoring of magnetic barcodes to programmable sites, as well as the selective latching of barcodes against background magnetic tags during flow. This approach may be used as a building block in micro‐ to macro‐scale magnetic interfaces.
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- Award ID(s):
- 1928326
- PAR ID:
- 10459311
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 6
- Issue:
- 24
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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