State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China.
Department of Applied Chemistry, National Chiao Tung University, Hsin-Chu 30010, Taiwan.
J Phys Chem B. 2022 Feb 17;126(6):1334-1340. doi: 10.1021/acs.jpcb.1c10305. Epub 2022 Feb 3.
Water, in addition to acting as a solvent, plays a constructional role in aqueous self-assembly. The hydrophobic molecule of POSS-PDI-POSS (POSS = polyhedral oligomeric silsesquioxanes, PDI = perylene diimide) has a shape anisotropy in which POSS is a ball-like bulky group and PDI is a flat aromatic group. The self-assembly of this molecule in water created assemblies with inner spaces due to the steric effect, which suppressed aromatic interactions of PDI and trapped water for the colloidal stability. By replacing POSS with dodecyl (C), C-PDI-C aggregated with extended aromatic interaction of PDI and less inner water. The resulting aggregates tended to agglomerate and precipitate. This discovery extended the scope of aqueous self-assembly by using the building blocks without amphiphilicity and created knowledge for biophysics.
水除了作为溶剂外，在水相自组装中还具有结构作用。POSS-PDI-POSS（POSS = 多面体低聚倍半硅氧烷，PDI = 苝二酰亚胺）的疏水分子具有形状各向异性，其中 POSS 是球状的庞大基团，PDI 是扁平的芳香基团。由于空间位阻效应，这种分子在水中的自组装形成了具有内部空间的组装体，抑制了 PDI 的芳环相互作用，并困住了水以实现胶体稳定性。通过用十二烷基（C）取代 POSS，C-PDI-C 通过 PDI 的扩展芳环相互作用和较少的内部水聚集。所得的聚集体倾向于聚集和沉淀。这一发现通过使用无两亲性的构建块扩展了水相自组装的范围，并为生物物理学创造了知识。
