Submitted to: Journal of Chromatography A
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2006
Publication Date: 9/6/2006
Citation: Peng, C., Ferreira, J.F., Wood, A.J. 2006. Direct analysis of artemisinin from "Artemisia annua" L. using high-performance liquid chromatography with evaporative light scattering detector, and gas chromatography with flame ionization detector. Journal of Chromatography A, 1133:254-258. Interpretive Summary: Artemisinin, a biologically active compound produced by sweet wormwood (Artemisia annua, Asteraceae) can be analyzed by several chromatographic methods. These methods include high-performance liquid chromatography (HPLC) combined with electrochemical detection (HPLC-EC), ultra-violet detection (HPLC-UV), or mass spectrometry (HPLC-MS); gas chromatography (GC) combined with flame ionization detection (GC-FID) or mass spectrometry (GC-MS). Artemisinin has light absorption characteristics that suggest that HPLC-UV is not sensitive to this compound. In the past, GC-FID methods were not efficient due to poor separation capability of existing columns, which made the separation of artemisinin from other related molecules (e.g., artemisinic acid and arteannuin B) difficult. HPLC-EC has been used in the past as the method of choice, but the EC detector does not detect certain artemisinin derivatives or precursors. This work compares HPLC with evaporative light scattering detection (HPLC-ELSD), a fairly recent class of detectors being used in the chromatographic field, with GC with flame ionization detection (GC-FID). Both methods detected artemisinin and related compounds. These methods are more efficient than HPLC-EC and HPLC-UV, and cheaper than HPLC-MS and GC-MS.
Technical Abstract: Since the isolation of artemisinin 32 years ago, it has been analyzed by different chromatographic techniques. This work compared the analysis of artemisinin from crude plant samples by GC with flame ionization detection (GC-FID) and HPLC with evaporative light scattering detector (HPLC-ELSD). However, data is presented indicating that GC is also suitable for the quantification of two of artemisinin precursors (arteannuin B and artemisinic acid) is a mass spectrometer is available. GC-FID and HPLC-ELSD were chosen because of their low cost compared to other detection methods, their ease of operation compared to HPLC with electrochemical detection, and because neither require artemisinin derivatization. Both GC-FID and HPLC-ELSD provided sensitive (ng level) and reproducible results for the analysis of artemisinin from field plants, with a correlation coefficient of r2= 0.86 between the two methods. Both methods could be easily adapted to the analysis of pharmaceutical-grade artemisinin.