The dynamics of giant unilamellar vesicle oxidation probed by morphological transitions
The dynamics of giant unilamellar vesicle oxidation probed by morphological transitions
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DOI：
10.1016/j.bbamem.2014.06.020
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发表时间：
2014-10-01
影响因子：
3.4
通讯作者：
Malmstadt, Noah
中科院分区：
文献类型：
--
作者：
Sankhagowit, Shalene;Wu, Shao-Hua;Malmstadt, Noah
我们研究了丽丝胺罗丹明B染料敏化诱导的1，2-二油酰甘油-3-磷酸胆碱（DOPC）巨单层囊泡（GUV）氧化的动力学，其中通过囊泡膜面积的变化来跟踪潜在的化学过程的进展。我们的球形GUV的表面积与体积比在短短10秒的照射后增加。膜面积扩张与高振幅波动相结合，这不是等渗条件下GUV的典型特征。为了精确测量变形和波动膜的面积，我们利用双光束光阱（DBOT）将GUV膜拉伸成几何规则的形状。进一步氧化导致囊泡收缩，GUV变得紧张，在双层中形成微米级孔。我们分析了GUV的形态学行为作为两个连续的限速步骤。我们还考虑了改变DOPC和1，2-二棕榈酰-sn-甘油基-3-磷酸乙醇胺-N-（丽丝胺罗丹明B磺酰基）（RhDPPE）浓度的影响。由此产生的动力学模型使我们能够测量脂质分子面积如何在氧化过程中变化，以及确定控制氧化产物形成速度的速率常数。受控的膜氧化导致透化也是基于工程化的含光敏剂的脂质囊泡的药物递送的潜在工具。(C)2014爱思唯尔有限公司版权所有。
We have studied the dynamics of Lissamine Rhodamine B dye sensitization-induced oxidation of 1,2-dioleoyl-snglycero-3-phosphocholine (DOPC) giant unilamellar vesicles (GUVs), where the progression of the underlying chemical processes was followed via vesicle membrane area changes. The surface-area-to-volume ratio of our spherical GUVs increased after as little as ten seconds of irradiation. The membrane area expansion was coupled with high amplitude fluctuations not typical of GUVs in isoosmotic conditions. To accurately measure the area of deformed and fluctuating membranes, we utilized a dual-beam optical trap (DBOT) to stretch GUV membranes into a geometrically regular shape. Further oxidation led to vesicle contraction, and the GUVs became tense, with micron-scale pores forming in the bilayer. We analyzed the GUV morphological behaviors as two consecutive rate-limiting steps. We also considered the effects of altering DOPC and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-(lissamine rhodamine B sulfonyl) (RhDPPE) concentrations. The resulting kinetic model allows us to measure how lipid molecular area changes during oxidation, as well as to determine the rate constants controlling how quickly oxidation products are formed. Controlled membrane oxidation leading to permeabilization is also a potential tool for drug delivery based on engineered photosensitizer-containing lipid vesicles. (C) 2014 Elsevier B.V. All rights reserved.