Cationic cyclotriveratrylene-based glycoconjugate and its interaction with fullerene
作者:Li-Juan Feng、Hui Li、Qi Chen、Bao-Hang Han
DOI:10.1039/c3ra40432c
日期:——
Fullerenes exhibit interesting biological activities both in vitro and in vivo. However, the low solubility of fullerenes in aqueous media appears to be a major problem for their biological application. To exploit water-soluble macrocyclic host systems to improve the water-solubility of fullerene, a cationic water-soluble CTV derivative containing glucosamine hydrochloride (CTV-GH) is synthesized and well characterized. The supramolecular complexation between CTV-GH and C60 was investigated in organic solvent and aqueous solution, respectively, and confirmed by fluorescence, UV-vis, and Raman spectra. The CTV derivative exhibits a distinct photoluminescence, which can be used to conveniently detect its interaction with C60 through spectrofluorometric titration. CTV-GH can bind C60 in toluene–DMSO solution with the association constant Ka = 4.36 × 105 M−1 calculated on the hypothesis of forming a supramolecular complex with 1 : 1 molar ratio at 298 K. In an aqueous solution, C60 has no absorption intensity due to its insolubility. However, in the presence of CTV-GH, a new characteristic peak of C60 at 342 nm in the UV-vis absorption spectrum was observed for the C60–CTV-GH complex and its intensity greatly increases over 24 h, which proves that CTV-GH can bind C60 in aqueous solution to form a water-soluble complex. The host–guest interaction between sugar-bearing CTV and C60 in aqueous solution will boost the potential biological applications of C60.
富勒烯在体外和体内都表现出有趣的生物活性。然而,富勒烯在水介质中的低溶解度似乎是其生物应用的一个主要问题。为了利用水溶性大环宿主系统来提高富勒烯的水溶性,我们合成了一种含有氨基葡萄糖盐酸盐的阳离子水溶性 CTV 衍生物(CTV-GH),并对其进行了表征。研究人员分别在有机溶剂和水溶液中考察了 CTV-GH 与 C60 的超分子络合,并通过荧光、紫外-可见光和拉曼光谱进行了证实。CTV 衍生物表现出明显的光致发光,可通过光谱荧光滴定法方便地检测其与 C60 的相互作用。CTV-GH 能在甲苯-DMSO 溶液中与 C60 结合,其结合常数 Ka = 4.36 × 105 M-1 是根据在 298 K 下形成摩尔比为 1 :在水溶液中,C60 由于不溶解而没有吸收强度。然而,在 CTV-GH 的存在下,C60-CTV-GH 复合物的紫外-可见吸收光谱在 342 纳米处出现了一个新的 C60 特征峰,且其强度在 24 小时内大幅增加,这证明 CTV-GH 可以在水溶液中与 C60 结合形成水溶性复合物。含糖 CTV 与 C60 在水溶液中的主客体相互作用将促进 C60 的潜在生物应用。