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Title: Magnifying the Structural Components of Biomembranes: A Prototype for the Study of the Self-Assembly of Giant Lipids
How bio-membranes are self-organized to perform their functions remains a pivotal issue in biological and chemical science. Understanding the self-assembly principles of lipid-like molecules hence becomes crucial. Here we report the meso-structural evolution of amphiphilic sphere-rod conjugates (giant lipids), and study the roles of geometric parameters (head-tail ratio and cross-section area) during this course. As a prototype system, giant lipids resemble natural lipidic molecules by capturing their essential features including head-tail configuration, monodispersed molecular weight distribution and minor interpenetration of hydrophobic tails. We demonstrate the self-assembly behavior of two categories of giant lipids (I-shape and T-shape, a total of 8 molecules). A rich variety of meso-structures are constructed in solution state and their molecular packing models are rationally understood. We streamline the driving forces of morphological evolution from both geometric and thermodynamic perspective. Giant lipids recast the phase behavior of both linear and branched lipidic molecules to certain degree, while the abundant self-assembled morphologies reveal distinct physiochemical behaviors when geometric parameters deviate from natural analogues.
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Angewandte Chemie
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National Science Foundation
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