Department of Chemical Engineering and Materials Science, Grad. Sch. of Engineering, University of Hyogo.
J Oleo Sci. 2022;71(3):353-362. doi: 10.5650/jos.ess21295.
Bicelles are extensively used as the parent assemblies of functional membrane materials. This study characterizes membrane fluidity in fatty acid/detergent bicelles containing carboxyl boron-dipyrromethene (BODIPY C12) and pyrromethene as fluorescent probe molecules. The anisotropy value of BODIPY C12 and pyrromethene in the phospholipid vesicles depended on the phase state of the vesicles. The anisotropy of the fluorescent probe molecules in bicelles of oleic acid/3-[(3-cholamidopropyl) dimethylammonio]-2-hydroxypropane sulfonate (OA/CHAPSO) was then evaluated. The OA/CHAPSO bicelles were prepared by mixing CHAPSO detergent solution with OA vesicles at different molar ratios, X (= [OA]/([OA]+[CHAPSO])). The anisotropies of the probes in the OA/CHAPSO bicelles increased with decreasing X . BODIPY C12 in the range 0.30 ≤ X ≤ 0.70 exhibited a distinctly larger anisotropy than pyrromethene. This result agreed with the increase in packing density associated with the adsorption of CHAPSO molecules on the OA bilayer membrane in the OA/CHAPSO bicelle, revealing that the anisotropy of BODIPY C12 molecule enables membrane-fluidity evaluation in OA/CHAPSO bicelles.
双分子层囊泡被广泛用作功能性膜材料的母体组装体。本研究以含有羧基硼-二吡咯甲川（BODIPY C12）和吡咯并吡咯作为荧光探针分子的脂肪酸/去污剂双分子层囊泡为模型，对膜流动性进行了研究。BODIPY C12 和吡咯并吡咯在磷脂囊泡中的各向异性值取决于囊泡的相态。然后评估了油酸/3-[(3-胆酰胺丙基)二甲氨基]-2-羟基丙磺酸（OA/CHAPSO）双分子层囊泡中荧光探针分子的各向异性。OA/CHAPSO 双分子层囊泡通过将 CHAPSO 去污剂溶液与 OA 囊泡以不同的摩尔比 X（= [OA]/([OA]+[CHAPSO])）混合制备。探针在 OA/CHAPSO 双分子层囊泡中的各向异性随 X 值的减小而增大。0.30 ≤ X ≤ 0.70 范围内的 BODIPY C12 表现出明显大于吡咯并吡咯的各向异性。这一结果与 CHAPSO 分子吸附在 OA 双层膜上引起的包装密度增加一致，表明 BODIPY C12 分子的各向异性能够评估 OA/CHAPSO 双分子层囊泡中的膜流动性。
