The distribution of Danqi tongmai tablet in rats at different timeframe by UHPLC-LTQ-orbitrap mass spectrometry and nanospray desorption electrospray ionization mass spectrometry imaging.

Danqi Tongmai tablet (DQTM), a combination of salvianolic acids (SA) and panax notoginsenosides (PNS), is developed for the treatment of cardiovascular diseases. However, the distribution of DQTM in vivo remained unclear. In the present study, a four-step approach was developed and applied for elucidating the migration of chemical constituents from DQTM to rat plasma and tissues. Firstly, the chemical components in DQTM were comprehensively characterized based on mass spectral tree similarity filter (MTSF) technique on LTQ-Orbitrap mass spectrometry. Secondly, the main chemical constituents absorbed into blood were identified with reference standards. Thirdly, the chemical constituents distributed in different tissues were characterized. Fourthly, the spatial distribution of main notoginsenosides in different tissues were explored by nano-spray desorption electrospray ionization mass spectrometry imaging (DESI-MSI), and the results of different administration methods were compared. As a result, 209 chemical constituents in DQTM were tentatively characterized, including 103 salvianolic acids and 106 notoginsenosides. Forty-two chemical constituents were unambiguously identified with reference standards in plasma. Meanwhile, 42 components in kidney, 40 in lung, 37 in heart, 38 in liver and spleen, and 30 in brain were identified. The results of DESI-MSI showed that notoginsenosides were primarily distributed in kidney, and slightly accumulated in brain, liver, lung, spleen and heart. Notoginsenosides were mainly distributed in the renal pelvis, and excreted at 1 h approximately after intravenous administration. In addition, there was no obvious accumulation effect between single dose and successive oral administration.