Hierarchical self-assembly of chiral fibres from achiral particles

Prybytak, P.; Frith, William J.; Cleaver, Douglas J.

doi:10.1098/rsfs.2011.0104

Cited by 19 publications

(34 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This effect may be induced with neither helical filament geometry nor discrete cross-linkers, but by simple energy minimization. Similar structural chirality has also previously been observed to emerge in simulations of discotic particles [37] and explored theoretically [35,38]. …”

Section: A Structural Chiralitysupporting

confidence: 79%

Designing highly tunable semiflexible filament networks

et al. 2014

View full text Add to dashboard Cite

Semiflexible polymers can generate a range of filamentous networks significantly different in structure from those seen in conventional polymer solutions. Our coarse-grained simulations with an implicit cross-linker potential show that networks of branching bundles, knotted morphologies, and structural chirality can be generated by a generalized approach independent of specific cross-linkers. Network structure depends primarily on filament flexibility and separation, with significant connectivity increase after percolation. Results should guide the design of engineered semiflexible polymers.

show abstract

Section: A Structural Chiralitysupporting

confidence: 79%

Designing highly tunable semiflexible filament networks

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Although challenging, such a capability is desirable for making functional materials efficiently. As illustrated by several theoretical studies recently (34)(35)(36), particles with anisotropic interactions could potentially offer an appealing route. Here we report our work using alternating current (AC) electric fields to direct the assembly of achiral building blocks, i.e., asymmetric colloidal dimers, into chiral clusters.…”

mentioning

confidence: 99%

Electric-field–induced assembly and propulsion of chiral colloidal clusters

Ma¹,

Wang²,

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

180

View full text Add to dashboard Cite

Chiral molecules with opposite handedness exhibit distinct physical, chemical, or biological properties. They pose challenges as well as opportunities in understanding the phase behavior of soft matter, designing enantioselective catalysts, and manufacturing single-handed pharmaceuticals. Microscopic particles, arranged in a chiral configuration, could also exhibit unusual optical, electric, or magnetic responses. Here we report a simple method to assemble achiral building blocks, i.e., the asymmetric colloidal dimers, into a family of chiral clusters. Under alternating current electric fields, two to four lying dimers associate closely with a central standing dimer and form both right-and left-handed clusters on a conducting substrate. The cluster configuration is primarily determined by the induced dipolar interactions between constituent dimers. Our theoretical model reveals that in-plane dipolar repulsion between petals in the cluster favors the achiral configuration, whereas outof-plane attraction between the central dimer and surrounding petals favors a chiral arrangement. It is the competition between these two interactions that dictates the final configuration. The theoretical chirality phase diagram is found to be in excellent agreement with experimental observations. We further demonstrate that the broken symmetry in chiral clusters induces an unbalanced electrohydrodynamic flow surrounding them. As a result, they rotate in opposite directions according to their handedness. Both the assembly and propulsion mechanisms revealed here can be potentially applied to other types of asymmetric particles. Such kinds of chiral colloids will be useful for fabricating metamaterials, making model systems for both chiral molecules and active matter, or building propellers for microscale transport.hirality is a fundamental concept presented ubiquitously in the molecular world. For example, small molecules such as the amino acids, phospholipids, and sugars with specific handedness build many biomacromolecules whose chirality is essential to living organisms. Although the right-and left-handed molecules are identical in chemical composition, the catalytic activity (1), pharmacological impact (2, 3), biological recognition (4), and optical response (5) can be strikingly different. Extending the chiral structure to microscopic objects such as colloids has become increasingly desirable for several reasons. First, the chiral arrangement of colloidal particles can exhibit unusually strong optical, electric, and magnetic responses (6-10) that are not manifested either at the single-particle level or in achiral forms. Therefore, chiral clusters can be potentially used to build metamaterials (11-14) with exotic properties or sensors for detection of molecules. Second, chiral particles can be conveniently characterized by real-time optical microscopy. As the macroscopic analog of chiral molecules, they can be used to study fundamental questions related to the crystallization (15) or enantiomeric separation (16, 17) of a racemic...

show abstract

“…For example, handed structures are observed in the simplest models of phyllotaxis (1) and self-assembly of biological fibers (2). In such models, there is no energetic distinction between and hence, a balance of the two enantiomers [that is, the right-handed (RH) and left-handed (LH) versions of the chiral structure].…”

mentioning

confidence: 99%

Coexistence of both gyroid chiralities in individual butterfly wing scales of Callophrys rubi

Winter

Butz

Dieker

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The wing scales of the Green Hairstreak butterfly Callophrys rubi consist of crystalline domains with sizes of a few micrometers, which exhibit a congenitally handed porous chitin microstructure identified as the chiral triply periodic single-gyroid structure. Here, the chirality and crystallographic texture of these domains are investigated by means of electron tomography. The tomograms unambiguously reveal the coexistence of the two enantiomeric forms of opposite handedness: the left-and right-handed gyroids. These two enantiomers appear with nonequal probabilities, implying that molecularly chiral constituents of the biological formation process presumably invoke a chiral symmetry break, resulting in a preferred enantiomeric form of the gyroid structure. Assuming validity of the formation model proposed by Ghiradella H (1989) J Morphol 202(1): 69-88 and Saranathan V, et al. (2010) Proc Natl Acad Sci USA 107(26):11676-11681, where the two enantiomeric labyrinthine domains of the gyroid are connected to the extracellular and intra-SER spaces, our findings imply that the structural chirality of the single gyroid is, however, not caused by the molecular chirality of chitin. Furthermore, the wing scales are found to be highly textured, with a substantial fraction of domains exhibiting the <001> directions of the gyroid crystal aligned parallel to the scale surface normal. Both findings are needed to completely understand the photonic purpose of the single gyroid in gyroid-forming butterflies. More importantly, they show the level of control that morphogenesis exerts over secondary features of biological nanostructures, such as chirality or crystallographic texture, providing inspiration for biomimetic replication strategies for synthetic self-assembly mechanisms.electron tomography | chirality | crystallographic texture | photonic crystal | butterfly wing scales A lthough the formation of chiral structures is fascinating, their occurrence can often be rationalized by simple energy or free energy considerations without a need to resort to their possible biological origin. For example, handed structures are observed in the simplest models of phyllotaxis (1) and self-assembly of biological fibers (2). In such models, there is no energetic distinction between and hence, a balance of the two enantiomers [that is, the right-handed (RH) and left-handed (LH) versions of the chiral structure]. Chiral symmetry breaking, the process by which one enantiomer occurs exclusively or with prevalence, is commonly observed in biological materials on a range of scales from molecular dimensions and the structure of DNA to the macroscopic size of snails (3). The dominance of one enantiomer is driven by the presence of a force or molecular building block that favors one enantiomer over the other; constituent chiral molecules (4), genetically controlled molecular pathways (3), and biological generation of torque (5) are possible causes.Here, we investigate the chiral symmetry breaking of the singlegyroid structure, a complex network-lik...

show abstract

Hierarchical self-assembly of chiral fibres from achiral particles

Cited by 19 publications

References 30 publications

Designing highly tunable semiflexible filament networks

Designing highly tunable semiflexible filament networks

Electric-field–induced assembly and propulsion of chiral colloidal clusters

Coexistence of both gyroid chiralities in individual butterfly wing scales of Callophrys rubi

Contact Info

Product

Resources

About