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Another interesting application of the electrospray interface not only demonstrates its efficacy for
natural product investigation but also shows some of the foibles that can be associated with the liquid
chromatography column. As a result of the contemporary popularity of herbal remedies in the United
States, there has been a demand for analytical techniques to monitor the substances imported, to ensure
their integrity and safety. Van Breeman et al. [24], developed an analytical method for measuring the
ginsenoside content of ginseng products, marketed as roots, capsules, tablets and liquid extracts.
Ginsenosides are made up of a series of triterpine saponins in proportions that are characteristic of their
country of origin. The individual ginsenosides have been separated by reverse phase chromatography
and ion exchange chromatography, but the use of specialized carbohydrate analysis columns, containing
aminopropyl functional groups, have also proved useful.

A. Ginsenoside standard added by direct infusion. B. Ginsenoside standard introduced from liquid
chromatograph C. Ginsenoside extract introduced from liquid chromatograph.

Figure 9.28
Electrospray Mass Spectra of ca 100 pmol of Ginsenoside
Reprinted with permission from R. B. van Breeman, C.R Huang,
Z. Z. Lu, A. Rimando, H. H. S. Fong and J. F. Fitzloff, Anal.
Chem., 67(21)(1995)3985., Copyright 1995 American Chemical Society