Lyotropic liquid crystal engineering–ordered nanostructured small molecule amphiphileself-assembly materials by design

Fong, Celesta; Le, Tu C.; Drummond, Calum J.

doi:10.1039/c1cs15148g

Cited by 288 publications

(221 citation statements)

References 210 publications

(350 reference statements)

Supporting

Mentioning

212

Contrasting

Unclassified

Order By: Relevance

“…Whilst ethanolamide-based amphiphiles are biologically relevant and have a range of commercial uses, particularly in the detergent and cosmetics industries, their physico-chemical behavior had, to date, remained poorly characterized. We have shown that small alterations to molecular structures can be used to design tailor-made amphiphiles with predictable phase behavior for specific applications such as drug delivery, cosmetic formulations, or household detergents [38].…”

Section: Discussionmentioning

confidence: 99%

“…As temperature increases, an increase in chain splay leads to a more cylindrical effective geometry and fluid lamellar phase formation. Furthermore, H-bond strength plays an important role in an amphiphiles ability to form inverse liquid crystalline phases such as the inverse hexagonal (H II ) and inverse cubic phases [26,29,32,37,38]. Strong, bifurcated H-bonding in the urea moiety dominates the lyotropic phase behavior of saturated urea amphiphiles resulting in extremely high curvature amphiphiles, which are only capable of forming an L 2 phase at high temperatures and hydration [28,30].…”

Section: Structure-property Correlationsmentioning

confidence: 99%

See 1 more Smart Citation

Nonionic diethanolamide amphiphiles with saturated hydrocarbon chains: Neat crystalline and lyotropic liquid crystalline phase behavior

Sagnella

Conn

Krodkiewska

et al. 2012

Journal of Colloid and Interface Science

Self Cite

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Section: Structure-property Correlationsmentioning

confidence: 99%

Nonionic diethanolamide amphiphiles with saturated hydrocarbon chains: Neat crystalline and lyotropic liquid crystalline phase behavior

Sagnella

Conn

Krodkiewska

et al. 2012

Journal of Colloid and Interface Science

Self Cite

View full text Add to dashboard Cite

“…Molecular self-assembly has been widely utilized to create nanostructured soft matter for applications in biomedicine as well as in electronics and optics. [1][2][3][4][5][6] In stimulus-responsive materials, molecular ordering can give rise to novel modes of activity. For example, the photoisomerization of azobenzene (AZO) motifs is used to generate dimension changes within aligned liquid crystalline (LC) networks.…”

Section: Introductionmentioning

confidence: 99%

Photoswitchable Nanomaterials Based on Hierarchically Organized Siloxane Oligomers

Zha

Vantomme

Berrocal

et al. 2017

Adv Funct Materials

View full text Add to dashboard Cite

Materials with highly ordered molecular arrangements have the capacity to display unique properties derived from their nanoscale structure. Here, the synthesis and characterization of azobenzene (AZO)-functionalized siloxane oligomers of discrete length that form photoswitchable supramolecular materials are described. Specifically, synergy between phase segregation and azobenzene crystallization leads to the self-assembly of an exfoliated 2D crystal that becomes isotropic upon photoisomerization with UV light. Consequently, the material undergoes a rapid athermal solid-to-liquid transition which can be reversed using blue light due to the unexpectedly fast 2D crystallization that is facilitated by phase segregation. In contrast, enabling telechelic supramolecular polymerization through hydrogen bonding inhibits azobenzene crystallization, and nanostructured pastes with well-ordered morphologies are obtained based on phase segregation alone, thus demonstrating block copolymer-like behavior. Therefore, by tailoring the balance of self-assembly forces in the azobenzene-functionalized siloxane oligomers, fast and reversible phase-changing materials can be engineered with various mechanical properties for applications in photolithography or switchable adhesion to lubricant properties. In these materials, contraction along the LC director occurs with isomerization of the planar trans-azobenzenes to the bent cis-azobenzenes. By limiting the depth of photoactivity, generally through utilizing the inherently high absorption coefficient of the azobenzenes, this contraction can give rise to anisotropic bending in poly mer films, [7,8] gels, [9] fibers, [10][11][12] and even crystals. [13] Different modes of motion arise with more complex molecular arrangements. For example, expansion of chiral nematic LCs along the helical axis has been utilized to create polymer coatings with photoswitchable topologies [14][15][16][17] and polymer films with macroscopic helical motion. [18] Additionally, polymer films with splay-bend configuration, in which LC-mesogens gradually change orientation throughout the film cross-section, have shown to exhibit inherently anisotropic bending as well as achieve significantly faster and larger bending when compared to uniaxially aligned films. [19][20][21] The ability of azobenzene photoisomerization to generate anisotropic dimension change and motion in LC networks typically results from increased molecular disorder caused by bent cis-azobenzene relative to networks with rod-like transazobenzene. Such photocontrol of order/disorder has been used to induce rapid nematic-to-isotropic phase transitions in LC films for applications in optical image storage [22] and holography. [23] The reversibility of azobenzene photoisomerization is beneficial for such applications, and the ability of azobenzene materials to undergo many trans-cis photoisomerization cycles without noticeable degradation in performance has been demonstrated. [24,25] Furthermore, few examples have demonstrated the photocontrolled swit...

show abstract

“…The crystallographic space group of this structure is P2 1 [23][24][25][26]. They consist of a lipid bilayer draped across a periodic minimal surface of zero mean curvature (figure 2 [27,28] grown in meso have been found to be robust and of high quality and TMPs crystallized within a lipidic cubic phase are more likely to retain their activity [30]. For in meso crystallization, monoolein (MO) is the most commonly used lipid to date [5,7,31].…”

Section: Introductionmentioning

confidence: 98%

Exploring the in meso crystallization mechanism by characterizing the lipid mesophase microenvironment during the growth of single transmembrane α-helical peptide crystals

Hag

Knoblich

Seabrook

et al. 2016

Phil. Trans. R. Soc. A.

Self Cite

View full text Add to dashboard Cite

The proposed mechanism for in meso crystallization of transmembrane proteins suggests that a protein or peptide is initially uniformly dispersed in the lipid self-assembly cubic phase but that crystals grow from a local lamellar phase, which acts as a conduit between the crystal and the bulk cubic phase. However, there is very limited experimental evidence for this theory. We have developed protocols to investigate the lipid mesophase microenvironment during crystal growth using standard procedures readily available in crystallography laboratories. This technique was used to characterize the microenvironment during crystal growth of the DAP12-TM peptide using synchrotron small angle X-ray scattering (SAXS) with a micro-sized X-ray beam. Crystal growth was found to occur from the gyroid cubic mesophase. For one in four crystals, a highly oriented local lamellar phase was observed, providing supporting evidence for the proposed mechanism for in meso crystallization. A new observation of this study was that we can differentiate diffraction peaks from crystals grown in meso, from peaks originating from the surrounding lipid matrix, potentially opening up the possibility of high-throughput SAXS analysis of in meso grown crystals.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'.

show abstract

Lyotropic liquid crystal engineering–ordered nanostructured small molecule amphiphileself-assembly materials by design

Cited by 288 publications

References 210 publications

Nonionic diethanolamide amphiphiles with saturated hydrocarbon chains: Neat crystalline and lyotropic liquid crystalline phase behavior

Nonionic diethanolamide amphiphiles with saturated hydrocarbon chains: Neat crystalline and lyotropic liquid crystalline phase behavior

Photoswitchable Nanomaterials Based on Hierarchically Organized Siloxane Oligomers

Exploring the in meso crystallization mechanism by characterizing the lipid mesophase microenvironment during the growth of single transmembrane α-helical peptide crystals

Contact Info

Product

Resources

About