The traditional Chinese medicine Paederia scandens has long been used in India, China and Vietnam for the treatment of toothache, chest pain, piles, inflammation of the spleen, rheumatic arthritis, and bacillary dysentery. Unfortunately, the analysis of active constituent in traditional Chinese medicine is a challenge for analytical chemist, because most of these compounds are in trace amounts.

In order to establish a reliable and fast analysis method, researchers in Dr. WU Zhijun lab at the Chengdu Institute of Biology, Chinese Academy of Sciences investigated the active constituents, that is iridoid glucosides, in P. scandens using high performance liquid chromatography and electrospray quadrupole time-of-flight-type tandem mass spectrometry (HPLC–ESI-QTOF). A total of 24 iridoid glucosides, including 14 new species, were identified or tentatively characterized.

A number of complex compounds were identified that contained a phenolic acid group in combination with iridoid and sugar moieties. Acylation of the 6-OH group of the sugar by phenolic acid was detected by the characteristicions at m/z 295, 265, and 235. Interestingly, the connection order between the asperuloside and paederoside moieties in the dimeric iridoid glucosides was confirmed by the characteristic productions at m/z 559. Notably, the connections are difficult to be confirmed even with the use of nuclear magnetic resonance spectroscopy.

The method is a rapid and new analysis method for the identification of iridoid glucoside in complex extract. This research entitled "Analysis of iridoid glucosides from Paederia scandens using HPLC–ESI-MS/MS" was published in Journal of Chromatography B on Jan. 10, 2013.