Self-assembly of β-alanine homotetramer: formation of nanovesicles for drug delivery.
Self-assembly of β-alanine homotetramer: formation of nanovesicles for drug delivery.
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β-丙氨酸同四聚体的自组装：形成用于药物输送的纳米囊泡。
DOI：
10.1039/c5tb00652j
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Alka Gupta
中科院分区：
文献类型：
--
作者：
R. Goel;Swarita Gopal;Alka Gupta
本文描述了在水介质中利用搅拌诱导β-丙氨酸四聚体（H2N-βAla-βAla-βAla-βAla -βAla- conh2）的自组装制备纳米囊泡的方法。动态光散射（DLS）研究揭示了平均粒径为~ 463 nm的纳米结构的形成。通过电子显微镜对纳米结构的形貌和尺寸进行了表征。结果显示，形成的球形纳米囊泡的尺寸范围为~ 100 nm至250 nm。利用圆二色性（CD）和红外光谱（IR）研究的二级结构估计表明，该四肽为分子内氢键构象。在自组装前后的水介质中进行的CD和IR研究描述了结构和氢键模式的显著变化。关于四肽的构象的支持性证据是通过使用计算方法的构象搜索提供的。理论预测的最小能量结构描述了一个8-螺旋型的主链折叠，形成了两个8元分子内氢键环。然后对四肽的四个短螺旋型链进行几何优化，从而形成一个具有中心腔的组装体，与实验结果完全一致。最后，研究人员评估了这些纳米囊泡作为强效抗帕金森药物左旋多巴载体的潜在用途。我们已经观察到，在水介质中，这些纳米囊泡能够包封左旋多巴分子，这是通过DLS测量以及吸收和发射光谱方法表明的。通过将pH值降低到6.2，这些装载的囊泡能够缓慢地释放药物。因此，这些组装物可被视为通常管理不善的左旋多巴的潜在运载工具。
The present paper describes the fabrication of nanovesicles using the stirring induced self-assembly of a β-alanine homotetramer (H2N-βAla-βAla-βAla-βAla-CONH2) in an aqueous medium. Dynamic light scattering (DLS) studies revealed the formation of nanostructures with an average particle size of ∼463 nm. The morphology and size of the nanostructures was also confirmed by electron microscopy. The formation of well-defined spherical nanovesicles in the size range of ∼100 nm to 250 nm is displayed. Secondary structure estimations using circular dichroism (CD) and infrared spectroscopic (IR) studies suggest an intramolecularly hydrogen bonded conformation for the tetrapeptide. CD and IR studies conducted in an aqueous medium before and after self-assembly depict a significant change in structure and hydrogen bonding patterns. Supportive evidence regarding the conformation of the tetrapeptide is provided by the conformational search using computational methods. The theoretically predicted minimum energy structure depicts an 8-helix type of backbone folding with the formation of two 8-membered intramolecularly hydrogen bonded rings. Four of the short helical type strands of the tetrapeptide were then subjected to a geometry optimization that resulted in the formation of an assembly with a central cavity, completely in agreement with experimental findings. Finally these nanovesicles were evaluated for their potential use as carriers of the potent anti-Parkinson's drug l-DOPA. We have observed that in aqueous media these nanovesicles are able to encapsulate the l-DOPA molecules, indicated by DLS measurements and also by absorption and emission spectroscopic methods. By lowering the pH to 6.2 these loaded vesicles are able to release the drug slowly. These assemblies thus can be considered as potential delivery vehicles for l-DOPA which normally suffers from poor administration.
影响因子：
8
作者：
Arnold, Ulrich;Huck, Bayard R.;Raines, Ronald T.
通讯作者：
Raines, Ronald T.
八聚体β-肽束的缓慢折叠-展开动力学。
影响因子：
4
作者：
Montalvo,GerondaL;Gai,Feng;Roder,Heinrich;DeGrado,WilliamF
通讯作者：
DeGrado,WilliamF