Stability of polymersomes prepared by size exclusion chromatography and extrusion
Stability of polymersomes prepared by size exclusion chromatography and extrusion
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DOI：
10.1016/j.colsurfa.2016.07.032
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发表时间：
2016-10-05
影响因子：
5.2
通讯作者：
Briscoe, Wuge H.
中科院分区：
文献类型：
--
作者：
Bartenstein, Julia E.;Robertson, James;Briscoe, Wuge H.
在这项工作中，研究了由两种不同分子量的聚合物（PBD32-PEO21和PBD125-PEO80）自组装的聚（丁二烯）-聚（环氧乙烷）（PBD-PEO）聚合体在纯水或磷酸盐缓冲盐水（PBS）中的稳定性。聚合体分散体通常表现出较大的多分散性，因此，如果需要窄尺寸分布，例如某些应用中的模型系统，则需要分离不同大小的囊泡。这通常是通过挤出具有指定孔径的膜来实现的，或者不太常见的是通过尺寸排除色谱（SEC）来实现。本研究发现，囊泡尺寸在100 ~ 5000 nm，多分散性指数(PDI) = 1时，聚合物分散体的挤出和SEC均可产生PDI < 0.35的小囊泡。使用SEC，可以分离不同大小的聚合体的组分。然而，随着时间的推移，SEC聚合体的大小，特别是扩散的大小显著增加，而挤出的聚合体则更稳定。我们将此归因于在SEC躲避过程中聚合体分散的可能稀释。进一步研究了温度和PBD-PEO分子量对挤出聚合体在纯水和磷酸盐缓冲液中抗稀释稳定性的影响。结果表明，低温、未稀释、磷酸盐缓冲液中制备的聚合体具有较高的稳定性，而聚合物分子量对其稳定性影响不大。(C) 2016年作者。这是一篇基于CC by许可的开放获取文章。
In this work, stability of poly(butadiene)-poly(ethylene oxide) (PBD-PEO) polymersomes, self-assembled from two polymers with different molecular weights (PBD32-PEO21 and PBD125-PEO80) in either pure H2O or phosphate buffered saline (PBS), is studied. Polymersome dispersions usually show large polydispersity, and it is thus desirable to separate different-sized vesicles if a narrow size distribution is required, e.g. for model systems in certain applications. This is typically achieved by extrusion through a membrane with a designated pore size or, less commonly, by size exclusion chromatography (SEC). Here, we find that both extrusion and SEC of polymersome dispersions with vesicle sizes ranging from 100 to 5000 nm and polydispersity index (PDI) = 1, can yield smaller vesicles with PDIs < 0.35. With SEC, it is possible to separate fractions of polymersomes with different sizes. However, the SEC polymersome size and particularly the spread in the size increase significantly over time, whereas the extruded polymersomes are shown to be more stable. We attribute this to possible dilution of the polymersome dispersion during the SEC elusion process. The effects of temperature and the PBD-PEO molecular weight on the stability of the extruded polymersomes against dilution in pure water and phosphate buffer are further studied. It is found that the polymersomes show higher stability when stored at lower temperature, undiluted, and prepared in phosphate buffer, whereas the polymer molecular weight does not have a large influence on the stability. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.