稳定同位素^13C标记富勒醇结构的探索  

Structural investigation of the stable isotope ^(13)C labeled fullerenol

作　　者：李红亮[1,2] 汪称龙 杨胜韬[1,2] 常雪灵[2] 

机构地区：[1]西南民族大学化学与环境保护工程学院,成都610041 [2]中国科学院高能物理研究所,中国科学院纳米生物效应与安全性重点实验室,北京100049

出　　处：《科学通报》2017年第16期1714-1720,共7页Chinese Science Bulletin

基　　金：国家自然科学基金(11475194);北京市自然科学基金(2152038);国家重点研发计划(2016YFA0201600)资助

摘　　要：富勒醇是具有良好生物相容性的富勒烯衍生物,因其具有低毒、抗肿瘤活性、抗病毒活性、抗氧化活性及光敏性等优势被广泛研究,发现其碳笼表面修饰的含氧基团决定其在生物医学应用中的生物效应.然而,富勒醇的结构比较复杂,尚未能精确描述.本文以稳定同位素^(13)C标记技术,通过富勒烯(C60)胺碱催化-氧化合成^(13)C骨架标记的富勒醇,结合质谱、红外光谱、X光电子能谱(XPS)及^(13)C核磁共振谱(^(13)C NMR)对其测试表征,探索富勒醇的精确结构.结果发现,稳定同位素^(13)C碳笼骨架标记极大地提高了^(13)C NMR信号强度,富勒醇分子结构的^(13)C NMR谱中清晰呈现出乙烯基醚碳、未反应烯碳、羟基化碳的信号,即不仅存在未氧化的碳和单氧化的碳,还存在高氧化的碳,与XPS测试结果吻合.富勒醇的碳笼表面修饰基团以羟基、半缩醛/酮、环氧以及羰基等结构存在.富勒醇复杂表面基团修饰结构的确定对其未来广泛的生物医学应用具有重要意义.Fullerenes are novel carbon nanomaterials that hold great promise in diverse areas, but the limited solubility make them hardly dispersible in aqueous environment and the applications in hydrophilic systems are restricted, in particular for biomedical areas. Currently, chemical functionalization is the main approach to increase the hydrophilicity of fullerenes, where the soluble fullerene derivatives show lower toxicity and interesting bio-effects. Among these fullerene derivatives, hydroxylated fullerene （fullerenol） has good biocompatibility, antitumor activity, antivirus activity, antioxidation activity and photosensitive activity, thus is widely studied and applied. The structure and functionalization of fullerenol determine the bio-effects in biomedical applications. However, the structure of fullerenol is very complicated and the precise structure of fullerenol has not been achieved yet, such as the hydroxyl group number, the position of functional groups and the chemical forms of surface groups. Herein, we adopted 13C staple isotope labeling to investigate the chemical structure of fullerenol. 13C-skeleton labeled fullerene C60 was prepared by arc discharge method. Then, 13C-C60 was hydroxylated by tetrabutylammonium hydroxide （TBAH） amine alkali catalysis-oxidation to obtain 13C-fullerenol. The 13C-fullerenol was characterized by TOF-MS, IR, X-ray photoelectron spectroscopy （XPS）, NMR to analyze the structure of fullerenol. The results indicated that 13C atoms were labeled on the skeleton of fullerene cage. Hydroxylation did not break the carbon cage, which was reflected by the strong C60 peak in the TOF-MS spectrum. The Poisson distribution of mass spectra indicated the isotopic effects and the skeleton labeling by 13C. Based on the TOF-MS, there were about five 13C atoms on each fullerene cage. The higher mass signals were assigned to the oxidized fullerene cage and the lack of very large mass signal suggested the detachment of functional groups during the laser irradiation. The oxygen conta

关 键 词：富勒醇 稳定同位素^13C标记 ^13C核磁共振谱 结构分析 

分 类 号：O613.71[理学—无机化学]