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[Fluorescence spectra of Dichroa febrifuga aqueous extraction]
Ying-hua Zhang1, Xun-li Shi, Ya-lan Liu
1College of Chemistry, Hebei Normal University, Shijiazhuang 050016, China.
Guang Pu Xue Yu Guang Pu Fen Xi = Guang Pu
|May 23, 2007
Summary
This study reveals that fluorescence spectroscopy can identify active quinazoline alkaloids in Dichroa febrifuga (chang shan). The method shows potential for both qualitative identification and quantitative analysis of this traditional Chinese medicine.
Area of Science:
- Analytical Chemistry
- Pharmacognosy
- Spectroscopy
Context:
- Dichroa febrifuga Lour (chang shan) is a traditional Chinese medicine.
- Quinazoline alkaloids are the active components responsible for its medicinal properties.
- Accurate identification and quantification are crucial for quality control.
Purpose:
- To investigate the fluorescence spectra of chang shan aqueous extracts.
- To explore the potential of three-dimensional fluorescence spectroscopy for qualitative and quantitative analysis of chang shan.
- To understand the influence of pH on the fluorescence properties.
Summary:
- Three distinct fluorescence peaks of quinazoline alkaloids were identified in chang shan extracts using 3D fluorescence spectroscopy at specific excitation (235, 270, 320 nm) and emission (430 nm) wavelengths.
- The fluorescence spectra exhibited pH-dependent changes, likely due to protonation of the beta-dichroine molecule.
- A linear relationship between fluorescence intensity and concentration was observed under near-neutral conditions, suggesting a viable quantitative method.
Impact:
- Establishes 3D fluorescence spectroscopy as a powerful "fingerprint" technique for qualitative identification of traditional Chinese medicine.
- Provides a foundation for developing a quantitative method for determining quinazoline alkaloid content in chang shan.
- Enhances quality control and standardization of Dichroa febrifuga preparations.
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