Protonation-Driven Aqueous Lyotropic Self-Assembly of Synthetic Six-Tail Lipidoids
Protonation-Driven Aqueous Lyotropic Self-Assembly of Synthetic Six-Tail Lipidoids
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DOI：
10.1021/acs.langmuir.0c01369
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发表时间：
2020-07-21
期刊：
影响因子：
3.9
通讯作者：
Mahanthappa, Mahesh K.
中科院分区：
文献类型：
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作者：
Jennings, James;Carter, Matthew C. D.;Mahanthappa, Mahesh K.
我们报告了质子化胺为基础的“类”，一类合成的脂质样分子，反映了多尾细菌两亲脂质A的基本结构特征的水溶致中间相行为。小角X射线散射（SAXS）研究表明，质子化的四（胺）头基的六尾类胡萝卜素在盐酸，硝酸，硫酸和磷酸的水溶液中的自组装驱动成层状（L-α）和反胶束（I-II）溶致液晶（LLC），这取决于酸的身份和浓度，两亲物的尾部长度和温度。在硫酸（aq）中形成的类脂质组装体表现出罕见的反体心立方（BCC）和反面心立方（FCC）胶束形态，后者意外地与零平均曲率L-α相共存。互补原子分子动力学（MD）模拟提供了详细的见解，这种不寻常的自组装行为。独特的水溶性溶致中间相行为的铵alcidoids起源于他们的二分法的能力，采取两个反锥形和扩链的分子构象取决于反离子的数量和他们的身份，这导致共存的超分子组装体具有显着不同的平均界面曲率。
We report the aqueous lyotropic mesophase behaviors of protonated amine-based "lipidoids," a class of synthetic lipid-like molecules that mirrors essential structural features of the multitail bacterial amphiphile lipid A. Small-angle X-ray scattering (SAXS) studies demonstrate that the protonation of the tetra(amine) headgroups of six-tail lipidoids in aqueous HCl, HNO3, H2SO4, and H3PO4 solutions variably drives their self-assembly into lamellar (L-alpha) and inverse micellar (I-II) lyotropic liquid crystals (LLCs), depending on acid identity and concentration, amphiphile tail length, and temperature. Lipidoid assemblies formed in H2SO4(aq) exhibit rare inverse body-centered cubic (BCC) and inverse face-centered cubic (FCC) micellar morphologies, the latter of which unexpectedly coexists with zero mean curvature L-alpha phases. Complementary atomistic molecular dynamics (MD) simulations furnish detailed insights into this unusual self-assembly behavior. The unique aqueous lyotropic mesophase behaviors of ammonium lipidoids originate in their dichotomous ability to adopt both inverse conical and chain-extended molecular conformations depending on the number of counterions and their identity, which lead to coexisting supramolecular assemblies with remarkably different mean interfacial curvatures.