Hollow nanocapsules prepared through stabilization of polymer vesicles formed from head-tail type polycations by introducing cross-linkages
Hollow nanocapsules prepared through stabilization of polymer vesicles formed from head-tail type polycations by introducing cross-linkages
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DOI：
10.1039/c1sm05075c
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发表时间：
2011-01-01
期刊：
影响因子：
3.4
通讯作者：
Kono, Kenji
中科院分区：
文献类型：
--
作者：
Harada, Atsushi;Ichimura, Shin-ichi;Kono, Kenji
通过在由聚酰胺-胺树枝状分子头部和聚-（L-赖氨酸）（PLL）尾部组成的头-尾型聚阳离子形成的聚合物囊泡中引入交联键，制备了中空纳米胶囊。PLL尾部通过赖氨酸残基与在两端带有环氧基团的寡聚（乙二醇）的反应交联。通过动态光散射（DLS）测量和透射电子显微镜观察证实了通过交联的中空结构的成功固定。通过DLS、zeta电位、荧光和圆二色性测量评价了纳米胶囊的pH依赖性。纳米胶囊的尺寸增加（即溶胀）是由于PLL尾部的螺旋构象响应于降低的pH或添加尿素而塌陷，表明PLL尾部的构象是决定纳米胶囊尺寸的关键因素。
Hollow nanocapsules were prepared through introduction of cross-linkages into polymer vesicles formed from head-tail type polycations composed of polyamidoamine dendron heads and poly-(L-lysine) (PLL) tails. The PLL tails were cross-linked by reaction of lysine residues with oligo(ethylene glycol) bearing epoxy groups at both ends. Successful fixing of hollow structures by crosslinking was confirmed by dynamic light scattering (DLS) measurements and transmission electron microscopy observation. The pH-dependent properties of the nanocapsules were evaluated by DLS, zeta-potential, fluorescence and circular dichroism measurements. The increase in the size (i.e. swelling) of the nanocapsules resulted from collapse of the helical conformation of PLL tails in response to decreased pH or addition of urea, indicating that the conformation of PLL tails was a crucial factor in determining the size of the nanocapsules.