运用二维相关红外光谱分析技术研究芦丁的热微扰过程

Study of Thermal Perturbation of Rutin by Two Dimensional Correlation Analysis and Fourier Transform Infrared Spectroscopy

采用傅里叶变换红外光谱法(FTIR)和二维相关分析(2D correlation analysis)技术研究了固态芦丁20℃～160℃的升温过程。实验结果显示,芦丁红外光谱的特征峰在红外图上随着温度升高变化不明显,说明实验中芦丁分子没有发生氧化反应。借助于二维相关分析.提高了谱图的分辨率,将芦丁分子中不同苯环的骨架振动峰在二维同步图上显示并区分开来。同时还揭示了芦丁分子内各官能团之间的相互作用,反映了在热微扰过程中这些基团之间的协同关系和变化的先后顺序。分析结果表明:芦丁分子中两个苯环,杂环的C=O及=C-O-C基团发生了相互作用。其变化的顺序是和含氧杂环相连的苯环,C=O,=C-O-C和含氧杂环相并的苯环。此结论与芦丁的氧化反应机理相一致。总之,二维相关红外分析可以作为研究芦丁热微扰过程中结构动态变化的一种新方法,也为芦丁在氧化过程中的机理研究提供了一个重要的理论依据。

The Fourier transform infrared (FTIR) spectroscopy and two-dimensional correlation analysis were applied to study the mini-heating process of the solid rutin from 20degreesC to 160degreesC. The changes of absorption peaks of rutin in the FTIR spectra of different temperatures were inconspicuous during heating up, which showed there were not oxidation reaction in rutin during the process. With the help of 2D correlation analysis, the resolution of the spectra was improved: the peaks of the two phenyl rings of rutin, which was overlapped in the FTIR spectrum, were separated into detached peaks in the 2D FTIR correlation spectra. Also the relationship among the different groups of rutin and the sequence of them to change during the oxidation process were reflected. The groups: C=O phenyl rings and =C-O-C of rutin have some relationship among each other, and the sequences of change were phenyl ring paralleled with the ring containing O, C=O, =C-O-C, phenyl ring linked with the ring containing O. The results are in good accordance with the oxidation mechanism of rutin. In conclusion, the 2D correlation analysis of FTIR can be a new method to analyze the microcosmic dynamic change of the structure of rutin during the mini-heating process and also offers a important theory gist to the study of oxidation mechanism of rutin.