Department of Physical Chemistry of Drugs, Faculty of Pharmacy, Comenius University in Bratislava, Odbojárov 10, 832 32, Bratislava, Slovakia.
Université Paris-Saclay, Laboratoire Léon Brillouin, UMR12 CEA-CNRS, CEA Saclay, F 91191, Gif-sur-Yvette Cedex, France.
Chem Phys Lipids. 2021 Sep;239:105118. doi: 10.1016/j.chemphyslip.2021.105118. Epub 2021 Jul 16.
In order to test an encapsulation method of short fragmented DNA (∼ 20-300 bp), we study the solubilisation in 150 mM solution of NaCl of a cubic phase formed by glycerol monooleate (GMO) with negatively charged dioleoylphosphatidylglycerol (DOPG) up to the level of unilamellar vesicles and, subsequently, the restoration of the cubic phase using Ca cations. We performed small angle X-ray and neutron scattering (SAXS and SANS) to follow structural changes in DOPG/GMO mixtures induced by increasing DOPG content. The cubic phase (Pn3m space group) is preserved up to ∼ 11 mol% of DOPG in DOPG/GMO. Above 20 mol%, the SANS curves are typical of unilamellar vesicles. The thickness of the DOPG/GMO lipid bilayer (d) decreases slightly with increasing fraction of DOPG. The addition of 15 mM of CaCl solution shields the electrostatic repulsions of DOPG molecules, increases slightly d and restores the cubic structures in the mixtures up to ∼ 37 mol% of DOPG. Zeta potential shows negative surface charge. The analysis of the data provides the radius of the water nano-channels of the formed non-lamellar structures. We discuss their dimensions with respect to DNA binding. In addition, Ca mediates DNA - DOPG/GMO binding. The formed hexagonal phase, H, binds less of DNA in comparison with cubic phases (∼ 6 wt% and ∼ 20 wt% of the total amount, respectively). The studied system can be utilized as anionic Q delivery vector for genetic material.
为了测试短片段 DNA（约 20-300bp）的封装方法，我们研究了在 150mM NaCl 溶液中单油酸甘油酯（GMO）与带负电荷的二油酰基磷脂酰甘油（DOPG）形成的立方相的溶解情况，直至形成单层囊泡，随后使用 Ca 阳离子恢复立方相。我们进行了小角 X 射线和中子散射（SAXS 和 SANS），以跟踪 DOPG/GMO 混合物中随着 DOPG 含量增加而引起的结构变化。立方相（Pn3m 空间群）在 DOPG/GMO 中保留至约 11mol%的 DOPG。超过 20mol%时，SANS 曲线是典型的单层囊泡。DOPG/GMO 脂质双层的厚度（d）随 DOPG 分数的增加略有减小。添加 15mM 的 CaCl2 溶液屏蔽了 DOPG 分子的静电排斥，略微增加了 d，并将混合物中的立方结构恢复至约 37mol%的 DOPG。Zeta 电位显示出负的表面电荷。数据分析提供了形成的非层状结构的水纳米通道的半径。我们讨论了它们的尺寸与 DNA 结合的关系。此外，Ca 介导 DNA-DOPG/GMO 的结合。与立方相相比，形成的六方相（H）结合的 DNA 较少（分别约为总 DNA 的 6wt%和 20wt%）。所研究的系统可用作遗传物质的阴离子 Q 传递载体。
