Bag Braja G, Ghorai Subrata, Panja Saikat K, Dinda Shaishab K, Paul Koushik
Department of Chemistry and Chemical Technology, Vidyasagar University Midnapore 721102 WB India
RSC Adv. 2018 Aug 16;8(51):29155-29163. doi: 10.1039/c8ra06488a. eCollection 2018 Aug 14.
Generation of vesicular self-assemblies from natural and synthetic components has been in the frontiers of research in recent years for an improved understanding of the self-assembly process and also because of its prospective and realized applications in the areas of advanced materials, biotechnology and medicine. In the present work, we report the first example of the generation of vesicular self-assemblies during an aerobic coupling reaction. The two precursor 2-naphthol units, having hydrogen bond donor-acceptor groups with appended alkyl chains, yielded binol (2,2'-dihydroxy-1,1'-binaphthyl) derivatives by aerobic coupling that spontaneously self-assembled , yielding vesicular self-assemblies and gels. The morphology of the self-assemblies has been characterized by various optical, electron and atomic force microscopic techniques. The vesicular self-assemblies obtained in the liquids were capable of entrapping fluorophores such as rhodamine-B and carboxy fluorescein including the anticancer drug doxorubicin. The entrapped fluorophores could also be released by sonication or by rupture of vesicles. The supramolecular gels obtained in binary solvent mixtures showed improved gelation abilities with increase in the alkyl chain lengths as reflected by their minimum gelator concentration (mgcs) values, gel to sol transition temperatures ( ) and rheology properties. The results described here are also the first demonstration of gelation during an aerobic coupling reaction.
近年来，利用天然和合成成分生成囊泡自组装体一直处于研究前沿，这不仅有助于深入理解自组装过程，还因其在先进材料、生物技术和医学领域的潜在及已实现的应用。在本工作中，我们报道了有氧偶联反应过程中生成囊泡自组装体的首个实例。两个带有氢键供体 - 受体基团且连接有烷基链的前体2 - 萘酚单元，通过有氧偶联反应生成联萘酚（2,2'-二羟基 - 1,1'-联萘基）衍生物，该衍生物能自发自组装，形成囊泡自组装体和凝胶。通过各种光学、电子和原子力显微镜技术对自组装体的形态进行了表征。在液体中获得的囊泡自组装体能够包封诸如罗丹明 - B和羧基荧光素等荧光团，包括抗癌药物阿霉素。包封的荧光团也可通过超声处理或囊泡破裂释放出来。在二元溶剂混合物中获得的超分子凝胶随着烷基链长度的增加表现出改善的凝胶化能力，这可从其最低凝胶剂浓度（mgcs）值、凝胶 - 溶胶转变温度（ ）和流变学性质反映出来。此处描述的结果也是有氧偶联反应过程中凝胶化的首次证明。
