Delorme N, Fery A
Max Planck Institute of Colloids and Interfaces, Wissenschaftpark Golm, 14424 Potsdam, Germany.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Sep;74(3 Pt 1):030901. doi: 10.1103/PhysRevE.74.030901. Epub 2006 Sep 5.
Mechanical properties of lipidic membranes such as their bending rigidity are governing liposome morphology and play an important role in processes like membrane fusion and adhesion. Force versus deformation measurements are the most direct means to determine this, but so far experimental data is scarce and mainly stems from techniques that are limited to giant vesicles. We present atomic force microscope force spectroscopy as a method allowing force-deformation measurements of submicron vesicles. Bending rigidities of small unilamellar dipalmitoylphosphatidylcholine (DPPC) liposomes (R<200 nm) can be derived from the force-deformation data using analytical models based on shell theory and are in good agreement with independent measurements.
脂质膜的力学性质，如其弯曲刚度，决定着脂质体的形态，并在膜融合和粘附等过程中发挥重要作用。力与变形测量是确定这一性质的最直接方法，但到目前为止，实验数据稀缺，且主要来自仅限于巨型囊泡的技术。我们提出原子力显微镜力谱法作为一种能够对亚微米级囊泡进行力-变形测量的方法。利用基于壳理论的分析模型，可以从力-变形数据中得出小单层二棕榈酰磷脂酰胆碱（DPPC）脂质体（半径<200 nm）的弯曲刚度，所得结果与独立测量结果吻合良好。
