真伪大黄的二维相关红外光谱

采用红外光谱法并结合二维相关光谱(two-dimensional correlation spectroscopy)分析技术，对药用西宁大黄和伪品华北大黄进行了无损快速鉴别研究。西宁大黄和华北大黄在一维谱图上差别不显著，而在二维谱图上显示出较大的差别。在1200-1700cm-1波段范围内，西宁大黄在同步图上有两个较强的自动峰，分别在1460和1560cm^-1附近，而华北大黄只有一个较强的自动峰，在1460cm^-1附近；同样在1030-1170cm-1波段范围内西宁大黄有两个较强的自动峰，分别在1060和1080cm^-1附近，而伪品大黄也只有一个较强的自动峰，在1080cm^-1附近。两个波段的异步谱也显示出较大的差别。结果表明：二维相关谱可以提高谱图的分辨率，增加谱图的识别能力，可用于药材真伪品的鉴别。该法快速、准确，为客观评价中药材的来源提供了一种新的方法。

Two-Dimensional Correlation Infrared Spectroscopy of Standard and False Dahuang

Standard Xining Dahuang (rheum tanguticum maxim.ex balf.) and false Huabei Dahuang (Rh:franzenbachii munt.) were identified fast and nondestructively by Fourier transform infrared spectroscopy (FTIR) combined with Two-dimensional correlation spectroscopy (2DCOS). The two kinds of Dahuang were similar to each other in one-dimensional IR spectra but quite different in 2D IR spectra. In the range between 1200 cm -1 and 1700 cm -1, two strong autopeaks were aroused by Xining Dahuang at 1460 and 1560 cm -1 in synchronous spectrum, whereas only one autopeak at 1460 cm -1 aroused by Huabei Dahuang. Also in the range between 1030 cm -1 and 1170 cm -1, two autopeaks were shown at 1060 and 1080 cm -1 in synchronous spectrum of Xining Dahuang, but only one autopeak at 1080 cm -1 in synchronous spectrum of Huabei Dahuang. It is proved that the 2D IR could be served in distinguishing standard and false medicinal herbs due to its unique advantages such as the high resolution and identification ability. Therefore, the fast and accurate property of 2D IR spectroscopy makes it a powerful and new approach for evaluating the medicinal herbs impersonally.