Tang Fan, Feng Hui, Du Yuqi, Xiao Yandi, Dan Hongxia, Zhao Hang, Chen Qianming
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, 610065; 610041, P. R. China.
XiangYa Stomatological Hospital, Central South University, Changsha, Hunan, 410000, P. R. China.
Chem Asian J. 2018 Jun 19. doi: 10.1002/asia.201800788.
Recently, supramolecular hydrogels have attracted increasing interest owing to their tunable stability and inherent biocompatibility. However, only few studies have been reported in the literature on self-healing supramolecular nucleoside hydrogels, compared to self-healing polymer hydrogels. In this work, we successfully developed a self-healing supramolecular nucleoside hydrogel obtained by simply mixing equimolar amounts of guanosine (G) and isoguanosine (isoG) in the presence of K . The gelation properties have been studied systematically by comparing different alkali metal ions as well as mixtures with different ratios of G and isoG. To this end, rheological and phase diagram experiments demonstrated that the co-gel not only possessed good self-healing properties and short recovery time (only 20 seconds) but also could be formed at very low concentrations of K . Furthermore, nuclear magnetic resonance (NMR), powder X-ray diffraction (PXRD), and circular dichroism (CD) spectroscopy suggested that possible G isoG -quartet structures occurred in this self-healing supramolecular nucleoside hydrogel. This co-gel, to some extent, addressed the problem of isoguanosine gels for the applications in vivo, which showed the potential to be a new type of drug delivery system for biomedical applications in the future.
近年来，超分子水凝胶因其可调谐的稳定性和固有的生物相容性而受到越来越多的关注。然而，与自愈合聚合物水凝胶相比，关于自愈合超分子核苷水凝胶的文献报道较少。在这项工作中，我们成功开发了一种自愈合超分子核苷水凝胶，它是通过在钾离子存在下简单混合等摩尔量的鸟苷（G）和异鸟苷（isoG）获得的。通过比较不同的碱金属离子以及不同G与isoG比例的混合物，系统地研究了凝胶化性质。为此，流变学和相图实验表明，该共凝胶不仅具有良好的自愈合性能和较短的恢复时间（仅20秒），而且可以在极低浓度的钾离子下形成。此外，核磁共振（NMR）、粉末X射线衍射（PXRD）和圆二色性（CD）光谱表明，在这种自愈合超分子核苷水凝胶中可能存在G-isoG四重结构。这种共凝胶在一定程度上解决了异鸟苷凝胶在体内应用的问题，显示出未来作为一种新型生物医学应用药物递送系统的潜力。
