Self-assembling biomaterials:: L-lysine-dendron-substituted cholesteryl-(L-lactic acid)(n)over-bar
Self-assembling biomaterials:: L-lysine-dendron-substituted cholesteryl-(L-lactic acid)(n)over-bar
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DOI：
10.1021/ma011964t
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发表时间：
2002-07-30
期刊：
影响因子：
5.5
通讯作者：
Stupp, SI
中科院分区：
文献类型：
--
作者：
Klok, HA;Hwang, JJ;Stupp, SI
本报告描述了一类新型的线性 - 树枝状嵌段共聚物的合成及其超分子组织。这些被称为棒 - 线团树枝状分子由一个胆固醇部分组成，该部分通过一种可生物降解的低聚（L - 乳酸）（$\overline{n}$）间隔基连接到三代不同的L - 赖氨酸树枝状结构上。虽然这些分子在干燥状态下排列非常无序，但在水合状态下观察到了不同的超分子形态。胆甾醇基 -（L - 乳酸）$(\overline{23})$ -（L - 赖氨酸）(G1)和胆甾醇基 -（L - 乳酸）$(\overline{23})$ -（L - 赖氨酸）(G2)自组装成层状结构，其周期性取决于水合程度。在低水合度下，胆甾醇基 -（L - 乳酸）$(\overline{22})$ -（L - 赖氨酸）(G3)也观察到层状排列。然而，在50 wt%的水含量下，高度水合的L - 赖氨酸树枝状结构中的空间位阻不再允许层状排列，并且形成了离散的纳米级聚集体。从动态光散射、电子显微镜和原子力显微镜获得了此类纳米聚集体形成的证据。这些棒 - 线团树枝状生物材料作为细胞和组织工程的临时分子支架可能具有潜在的研究价值。
This report describes the synthesis and supramolecular organization of a novel class of linear-dendritic block copolymers. The molecules, which are termed rodcoil dendrons, consist of a cholesterol moiety that is attached to L-lysine dendrons of three different generations via a biodegradable oligo(L-lactic acid)((n) over bar), spacer. Whereas the molecules exhibit very poor ordering in the dry state, different supramolecular morphologies were observed in the hydrated state. Cholesteryl(L-lactic acid)((23) over bar)-(L-lysine)(G1) and cholesteryl-(L-lactic acid)((23) over bar)-(L-lysine)(G2) self-assemble into lamellar structures with periodicities that depend on degree of hydration. At low degrees of hydration, lamellar ordering was also observed for cholesteryl-(L-lactic acid)((22) over bar)-(L-lysine)(G3). However, at 50 wt %, water steric hindrance in the highly hydrated L-lysine dendrons no longer allows lamellar ordering, and discrete nanosized aggregates are formed. Evidence for the formation of such nanoaggregates was obtained from dynamic light scattering, electron microscopy, and atomic force microscopy. These rodcoil dendron biomaterials could be of potential interest as temporary molecular scaffolds for cell and tissue engineering.