A simplified strategy for molecular formula determination of chemical constituents in traditional Chinese medicines based on accurate mass, A + 1 and A + 2 isotopic peaks using Fourier transform ion cyclotron resonance mass spectrometry

Abstract

Rationale Recently, isotopic fine structures derived from Fourier transform ion cyclotron resonance mass spectrometry have been used to determine the molecular formula for unknown compounds in many complex systems. However, a simplified strategy for molecular formula determination of chemical constituents in traditional Chinese medicines (TCMs) based on accurate mass, A + 1 and A + 2 isotopic peaks is necessary. Methods Salviae miltiorrhizae was selected as a representative species. First, the chemical constituents were chromatographically separated and their accurate masses were obtained. The A + 1 and A + 2 isotopic peaks of all chemical constituents were then also acquired. Finally, the chemical formulae of the chemical constituents were determined. Results In the sample of Salviae miltiorrhizae, the formulae of 38 CHO‐containing chemical constituents were quickly determined, and all chemical constituents were identified using their tandem mass spectrometric data. Moreover, the method was validated by comparison of the A + 1 and A + 2 isotopic peaks, their fragmentation patterns and the retention times of six selected standard substances. Conclusions The results demonstrate that the described strategy performs well for molecular formula determination of chemical constituents in TCMs. This also indicates that this method will be meaningful for the structural identification of chemical constituents of TCMs.

Full collision energy ramp‐MS2 spectral features of natural esters: Salvianolic acid A as a case

“…1 Here, we evaluate whether the MS/MS patterns of esters are comparable with those of peptides. In particular, full collision energy ramp-MS 2 (FCER-MS 2 ) spectrum 2 implies that all information on fragment ions, such as high-resolution m/z (HR-m/z), optimal collision energy (OCE), and maximal relative ion intensity (RII max ), is constructed for a representative natural ester, namely salvianolic acid A (SA), which is a primary contributor to the therapeutic spectrum of a well-known herbal medicine, namely Salviae Miltiorrhizae Radix et Rhizoma (Chinese name: Danshen), 3 to illustrate the empirical properties.…”