采用傅里叶变换红外光谱(FTIR)及其二阶导数谱和二维相关红外光谱对传统名贵中药材肉苁蓉、管花肉苁蓉和盐生肉苁蓉进行鉴别研究。结果表明,肉苁蓉与管花肉苁蓉的红外谱图有明显区别,相似系数仅0.6233;而肉苁蓉与盐生肉苁蓉的峰形和峰位均极其相似,相似系数达0.9048,仅从一维图上无法看出两者的成分差异,但通过二阶导数谱中1730(1738),816cm^-1。处的峰形差异可发现二者的一些成分含量存在较明显差异。二维相关谱更直观地反映出三者的差异,它们的自动峰个数均不相同。可见,红外光谱法基本可以实现了对肉苁蓉属3种药材的鉴别,而且具有快速、有效和无损等优点。
In the present paper, Fourier transform infrared spectroscopy (FTIR) associated with second derivative infrared spectroscopy and two-dimensional correlation spectroscopy (2D-IR) were used to analyze the 3 different sources of Hebra cistanche. The results showed that these IR spectra showed their different macro-fingerprint features: the charactersistic peaks of C. deserticola were located at -1 730, 1 633, 1 156, 1 081, 1 025 and 931 cm^-1 and those of C. tubulosa were at 1 692, 1 631, 1 604, 1 516, 1 265 and 1 023 cm^-1 , respectively. The only two peaks at -1 151 and 1 085 cm 1 of C. salsa were different from that of C. deserticola. As a result, the IR spectrum of C. deserticola could be identified obviously from that of the C. tubulosa, whose similar index was only 0. 623 3, but it was very similar to that of C. salsa, whose similar index was up to 0. 904 8, demonstrating very similar ingredients. However, the difference between C. deserticola and C. salsa was obvious in the second derivative IR spectra: the shape of the two peaks of C. deserticola at -1 730 and 816 cm^-1 were much sharper. In addition, the fingerprint characters in 2D-IR spectra were more visualized. The three kinds of herbs were quite different from each other in the number and intensity of autopeaks. Therefore, FTIR macro-fingerprint method can identify different sources of Hebra cistance fast, nondestructively and effectively.