State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116024, China.
Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
Angew Chem Int Ed Engl. 2021 Oct 25;60(44):23569-23573. doi: 10.1002/anie.202108076. Epub 2021 Aug 23.
Organic self-assembled co-crystals have garnered considerable attention due to their facile synthesis and intriguing properties, but supramolecular interactions restrict their stability in aqueous solution, which is especially important for biological applications. Herein, we report on the first biological application of aqueous dispersible self-assembled organic co-crystals via the construction of metal-organic framework (MOF) -stabilized co-crystals. In particular, we built an electron-deficient MOF with naphthalene diimide (NDI) as the ligand and biocompatible Ca as the metal nodes. An electron donor molecule, pyrene, was encapsulated to form the host-guest MOF self-assembled co-crystal. We observed that such MOF structure leads to uniquely high-density ordered arrangement and the close intermolecular distance (3.47 Å) of the charge transfer pairs. Hence, the concomitant superior charge transfer interaction between pyrene/NDI can be attained and the resultant photothermal conversion efficiency of Py@Ca-NDI in aqueous solution can thus reach up to 41.8 %, which, to the best of our knowledge, is the highest value among the reported organic co-crystal materials; it is also much higher than that of the FDA approved photothermal agent ICG as well as most of the reported MOFs. Based on this realization, as a proof of concept, we demonstrated that such a self-assembled organic co-crystal platform can be used in biological applications that are exemplified via highly effective long wavelength light photothermal therapy.
有机自组装共晶由于其易于合成和有趣的性质而受到广泛关注，但超分子相互作用限制了它们在水溶液中的稳定性，这对于生物应用尤为重要。在此，我们通过构建金属-有机框架（MOF）稳定的共晶，报告了第一个在水溶液中分散的自组装有机共晶的生物应用。具体而言，我们构建了一个以萘二酰亚胺（NDI）为配体、生物相容性 Ca 为金属节点的缺电子 MOF。封装了一个电子给体分子芘，形成主客体 MOF 自组装共晶。我们观察到，这种 MOF 结构导致电荷转移对的高密度有序排列和紧密的分子间距离（3.47 Å）。因此，可以获得芘/NDI 之间协同的优异电荷转移相互作用，并且在水溶液中 Py@Ca-NDI 的光热转换效率因此可以达到 41.8%，据我们所知，这是报道的有机共晶材料中的最高值；它也远高于 FDA 批准的光热试剂 ICG 以及大多数报道的 MOFs。基于这一认识，作为概念验证，我们证明了这种自组装有机共晶平台可用于生物应用，例如高效的长波长光热疗。
