Dos Santos Silva Araújo Larissa, Watson Leah, Traore Daouda A K, Lazzara Giuseppe, Chiappisi Leonardo
Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Viale delle Scienze pad 17, 90128, Palermo, Italy.
Institut Max von Laue - Paul Langevin, 71 Avenue des Martyrs, 38042, Grenoble, France.
Soft Matter. 2022 Sep 14;18(35):6529-6537. doi: 10.1039/d2sm00807f.
In this work, the inclusion complexes of alkyl ethoxy carboxylates with α-cyclodextrin (αCD) and β-cyclodextrin (βCD) were investigated. The thermodynamics of the complexation process was probed by isothermal titration calorimetry (ITC) and volumetry as a function of the degree of ionization of the surfactant. The complexation process was shown to be an enthalpically driven pH-independent process. For both types of cyclodextrins, the complexes were found to spontaneously self-assemble into highly-ordered supramolecular aggregates probed by small-angle neutron scattering and electron and optical microscopy. Herein, we report the formation of thin platelets for nonionized surfactant systems and equally spaced multilayered hollow cylinders for ionized systems in a hierarchical self-assembly process. In addition, the analysis allowed unveiling the effect of the number of ethylene oxides in the surfactants and the CD cavity size on the morphology of the aggregates. Finally, this study also highlights the importance of examining the tuning parameters' influence on the short and long-range interactions involved in the control of the assembly process.
在本研究中，对烷基乙氧基羧酸盐与α-环糊精（αCD）和β-环糊精（βCD）的包合物进行了研究。采用等温滴定量热法（ITC）和体积法，研究了络合过程的热力学，该过程是表面活性剂电离度的函数。结果表明，络合过程是一个由焓驱动的与pH无关的过程。对于这两种类型的环糊精，通过小角中子散射、电子显微镜和光学显微镜研究发现，络合物能自发地自组装成高度有序的超分子聚集体。在此，我们报道了在分级自组装过程中，非离子表面活性剂体系形成薄片状晶体，离子化体系形成等间距的多层空心圆柱体。此外，通过分析揭示了表面活性剂中环氧乙烷的数量和环糊精空腔大小对聚集体形态的影响。最后，本研究还强调了研究调节参数对控制组装过程中涉及的短程和长程相互作用的影响的重要性。
