Department of Chemistry, Indian Institute of Technology Tirupati, Settipalli Post, Tirupati - 517506, Andhra Pradesh, India.
Chem Commun (Camb). 2022 May 20;58(41):6044-6063. doi: 10.1039/d2cc01850k.
Host-guest chemistry, particularly of supramolecules, has been an intriguing topic for researchers for a long time due to its multiplicative applications ranging from chemical to biological to materials science. Supramolecules, such as calixarenes, are excellent host molecular systems due to their controllable cavity along with the ease of functionalization both at the lower and upper rims. The host-guest interactions involving calixarenes have been primarily studied using physical methods, such as absorption, fluorescence and nuclear magnetic resonance spectroscopy, isothermal titration calorimetry and mass spectrometry. The corresponding literature as disseminated through review articles triggered broadening of the spectrum of research. Depending upon the nature of the derivatization, the supramolecular conjugates of calixarenes have been shown to form different morphologies of micro and nanometric size as reported in the literature. Pertinent research performed in our own group was based on atomic force microscopy, transmission electron microscopy and scanning electron microscopy studies. The literature reveals that such morphologies are modified in the presence of guest species. Thus, the supramolecular host-guest complexation of calixarenes leading to the formation of various architectures has been studied using both spectroscopy and microscopy techniques to obtain complimentary data. However, there are no review articles that provide discussions on this exciting area of supramolecular science involving microscopy. Therefore, in the present article, for the first time, we have brought together the research reported in the literature during the past decade, including ours, in demonstrating the supramolecular architectures formed from the host-guest interactions extended by the conjugates of calixarenes, and their applications using microscopy. The scope of this article spans across various features of interaction in these systems: (i) in solution, (ii) at the air-water interface and (iii) on solid surfaces. The application domain includes sensing of organic explosives and drugs, exhibiting antibacterial activity, supramolecular self-assembly or co-assembly resulting in gels, micelles and vesicles, and the consequent aggregation-induced emission and a few others.
主体-客体化学，特别是超分子化学，由于其在化学、生物和材料科学等领域的应用具有倍增效应，长期以来一直是研究人员感兴趣的课题。杯芳烃等超分子是出色的主体分子体系，因为它们的空腔可以控制，并且在较低和较高边缘都很容易进行功能化。主体-客体相互作用主要使用物理方法（如吸收、荧光和核磁共振波谱、等温滴定量热法和质谱法）进行研究。通过综述文章传播的相应文献引发了研究范围的扩大。根据衍生化的性质，超分子杯芳烃缀合物已被证明在文献中形成不同形态的微纳米尺寸。我们自己的小组进行的相关研究基于原子力显微镜、透射电子显微镜和扫描电子显微镜研究。文献表明，在客体物种存在的情况下，这些形态会发生变化。因此，使用光谱学和显微镜技术研究了杯芳烃的主体-客体超分子络合作用，以形成各种结构，以获得补充数据。然而，没有综述文章讨论涉及显微镜的这一令人兴奋的超分子科学领域。因此，在本文中，我们首次汇集了过去十年中包括我们自己的研究报告的文献，展示了由杯芳烃缀合物的主体-客体相互作用延伸形成的超分子结构，以及使用显微镜的应用。本文的范围涵盖了这些体系中相互作用的各种特征：（i）在溶液中，（ii）在空气-水界面上，（iii）在固体表面上。应用领域包括对有机炸药和药物的传感、表现出抗菌活性、超分子自组装或共组装导致凝胶、胶束和囊泡，以及随后的聚集诱导发射等。
