Discrimination of different genuine Danshen and their extracts by Fourier transform infrared spectroscopy combined with two-dimensional correlation infrared spectroscopy

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2012-11, Vol.97, p.290-296
• Main Authors: Liu, Xin-hu, Xu, Chang-hua, Sun, Su-qin, Huang, Jian, Zhang, Ke, Li, Guo-yu, Zhu, Yun, Zhou, Qun, Zhang, Zhi-cheng, Wang, Jin-hui
• Format: Article
• Language: English
• Subjects: Danshen; Discrimination; Fourier-transform infrared spectroscopy (FT-IR); Second derivative IR spectra (SD-IR); Two-dimensional correlation infrared spectroscopy (2D-IR)
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2012.06.013

[Display omitted] ► Different genuine Danshen were analyzed by infrared spectroscopy. ► Differences were discriminated by a three-step of infrared spectroscopy completely. ► The analysis results by infrared spectroscopy were verified by UPLC. In this study, six varieties of Danshen from different populations and genuine (“Daodi” in Chinese transliteration) regions were discriminated and identified by a three-step infrared spectroscopy method (Fourier transform-infrared spectroscopy (FT-IR) coupled with second derivative infrared spectroscopy (SD-IR) and two dimensional correlation infrared spectroscopy (2D-IR)). Though only small differences were found among the FT-IR spectra of the six Danshen samples, the positions and intensities of peaks at 3393, 3371, 1613, 1050, and 1036cm−1 could be considered as the key factors to discriminate them. More significant differences were exhibited in their SD-IR, particularly for the peaks around 1080, 1144, 695, 665, 800, 1610, 1510, 1450, 1117 and 1077cm−1. The visual 2D-IR spectra provided dynamic chemical structure information of the six Danshen samples with presenting different particular auto-peak clusters, respectively. Moreover, the contents of salvianolic acid B in all samples were measured quantitatively by a validated ultra performance liquid chromatography (UPLC), which was consistent with the FT-IR findings. This study provides a promising method for characteristics and quality control of the complicated and extremely similar herbal medicine like Danshen, which is more cost effective and time saving.