Gellert Florian, Ahrens Heiko, Wulff Harm, Helm Christiane A
Institute of Physics, University of Greifswald, Felix-Hausdorff-Straße 6, D-17489 Greifswald, Germany.
Membranes (Basel). 2022 Jul 8;12(7):698. doi: 10.3390/membranes12070698.
The lateral movement in lipid membranes depends on their diffusion constant within the membrane. However, when the flux of the subphase is high, the convective flow beneath the membrane also influences lipid movement. Lipid monolayers of an unsaturated fatty acid at the water-air interface serve as model membranes. The formation of domains in the liquid/condensed coexistence region is investigated. The dimension of the domains is fractal, and they grow with a constant growth velocity. Increasing the compression speed of the monolayer induces a transition from seaweed growth to dendritic growth. Seaweed domains have broad tips and wide and variable side branch spacing. In contrast, dendritic domains have a higher fractal dimension, narrower tips, and small, well-defined side branch spacing. Additionally, the growth velocity is markedly larger for dendritic than seaweed growth. The domains' growth velocity increases and the tip radius decreases with increasing supersaturation in the liquid/condensed coexistence region. Implications for membranes are discussed.
脂质膜中的横向运动取决于其在膜内的扩散常数。然而，当亚相的通量较高时，膜下方的对流也会影响脂质的运动。水-空气界面处不饱和脂肪酸的脂质单分子层可作为模型膜。研究了液/凝聚共存区域中畴的形成。畴的尺寸是分形的，并且它们以恒定的生长速度生长。增加单分子层的压缩速度会诱导从海藻状生长向树枝状生长的转变。海藻状畴具有宽阔的尖端和宽且可变的侧枝间距。相比之下，树枝状畴具有更高的分形维数、更窄的尖端和小且明确的侧枝间距。此外，树枝状生长的生长速度明显大于海藻状生长。在液/凝聚共存区域中，随着过饱和度的增加，畴的生长速度增加且尖端半径减小。文中讨论了其对膜的影响。
