Deconvolution of overlapped peaks in total ion chromatogram of essential oil from citri reticulatae pericarpium viride by automated mass spectral deconvolution & identification system / 中国中药杂志

This experiment shows how to use the automated mass spectral deconvolution & identification system (AMDIS) to deconvolve the overlapped peaks in the total ion chromatogram (TIC) of volatile oil from Chineses materia medica (CMM). The essential oil was obtained by steam distillation. Its TIC was gotten by GC-MS, and the superimposed peaks in TIC were deconvolved by AMDIS. First, AMDIS can detect the number of components in TIC through the run function. Then, by analyzing the extracted spectrum of corresponding scan point of detected component and the original spectrum of this scan point, and their counterparts' spectra in the referred MS Library, researchers can ascertain the component's structure accurately or deny some compounds, which don't exist in nature. Furthermore, through examining the changeability of characteristic fragment ion peaks of identified compounds, the previous outcome can be affirmed again. The result demonstrated that AMDIS could efficiently deconvolve the overlapped peaks in TIC by taking out the spectrum of matching scan point of discerned component, which led to exact identification of the component's structure.

Determination of sulfur dioxide in traditional Chinese medicine by derivative fluorometry / 中国中药杂志

<p><b>OBJECTIVE</b>To establish a derivative fluorometry method for the determination of sulfur dioxide residues in traditional Chinese medicine.</p><p><b>METHOD</b>The optimal derivation condition was established. The fluorescence intensity was detected at excitation wavelength of 321 nm, and emission wavelength of 384 nm.</p><p><b>RESULT</b>A linear relationship was obtained between the fluorescence intensity and the addition of reference substance in the range of 0.999 7-17.99 nmol with a correlation coeffient of 0.999 9, and the average recovery was 102.3% with RSD 4.6%.</p><p><b>CONCLUSION</b>This method is simple and sensitive with quick and correct result. It can provide a reference for the determination of sulfur dioxide residues in traditional Chinese medicine.</p>