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A liquid chromatography/sonic spray ionization mass spectrometry method (LC/SSI-MS) was developed for qualitative and quantitative analyses of ginkgo terpene trilactones. Five ginkgo terpene trilactones were successfully protonated for qualitative and quantitative analyses under the study conditions. The typical ion adducts were identified as (M + H)+, (M + NH4)+, and (M + Na)+. The limits of detection were achieved between 2.5 and 10 ng with RSD of 0.173-4.82% and a linear range of 10-80 ng with R² = 0.991-0.999. This method was used to identify and quantify ginkgo terpene trilactones in extractions of ginkgo biloba leaves obtained from three different extraction methods. This is the first completely validated LC/MS method for quantification of ginkgo terpene trilactones. The factors that contributed to reduce the errors of identification and quantification of ginkgo terpene frilactones are systematically reported, and the advantages and disadvantages of LC/MS method in quantitative analysis are also discussed. [ABSTRACT FROM AUTHOR]

A method was developed for the extraction and quantification of pharmacologically active terpene trilactones (ginkgolides, bilobalide) from the tissues of Ginkgo biloba L. and pharmaceutical ginkgo products by RP- HPLC, based on the theory of terpene trilactones ionization. Four ginkgolides (GA, GB, GC, GJ) and biobalide (BB) from both the ginkgo leaves and commercially available ginkgo extracts were quantitatively extracted by using this method. The recovery rate of the method was 97.5- 100% with RSD of 1.2-2.8%. The detection limit was 0.05-0.1 μg, and the linear range was 0.1-12 μg. This detection limit represents a marked improvement over previously reported methods, suggesting the new method is a viable technique for routine analysis of ginkgo terpene trilactones in natural and commercial samples. The method reported by van Beek et al. in 1991 (van Beek, T.A.; Scheeren, H. A.; Rantio T.; Melger, W. C.; Lelyveld, G. P. J. Chromatogr. 1991,543,375-387.) was used as a reference method to monitor the accuracy of extraction and analysis in this study. SSI-MS technique was used to identify isolated target components. Carbohydrase treatment and solubility of terpene trilactones in various solvents were also discussed. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the ozonolytic decomposition of terpenoids and terpenes, during sampling on Tenax, in an artificial air system at ambient concentration levels. Dependence of detrimental effect of 8-150 ppbv on chemical structure of compounds; Enhancement of analytical recoveries for many compounds when sampling duration is reduced from 10 minutes to 30 seconds.