Artemisinin determination and degradation in soil using supercritical fluid extraction and HPLC-UV
Artemisinin, a bioactive compound produced in Artemisia annua L. (sweet wormwood) is used as active ingredient in drugs against malaria. Cultivation of A. annua at field scale implies high amounts of artemisinin produced and potential high losses to soil with impact to vulnerable organisms in soil and leaching to the aquatic environment. A new method was developed for extraction of artemisinin in sandy, clayey and humic soil samples by supercritical fluid extraction (SFE) and determination by HPLC. Optimal SFE conditions were reached using ethanol as modifier at a flow of 0.5 mL min-1 and a total extraction time of 20 min. The HPLC method had linearity up to >535 mg kg-1 for all soil types, limit of detection (LOD) was 13 µg kg-1 soil and limit of quantification (LOQ) was 43 µg kg-1 soil. Recovery for soil samples spiked with artemisinin 1 h before extraction was determined to 70-80%. No matrix effect was observed in the detection. The method enabled quantification of artemisinin in three common soil types, and was applied for determination of degradation kinetics of artemisinin in spiked soils. Degradation kinetics consisted of an initial fast degradation followed by a slower one. The slower reaction could be fitted by first-order kinetics resulting in rate constants of 0.05, 0.084 and 0.32 per day in sandy, clayey and humic soil, respectively. Both the rate of the fast and slow reaction appeared to increase with soil organic matter content. The relative long persistence time in soil increases the risk of toxic effects on non target organisms in soil as well as in water.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media
Document Type: Research Article
Faculty of Life Sciences (LIFE), Department of Basic Sciences and Environment, University of Copenhagen, Frederiksberg, Denmark
Faculty of Life Sciences (LIFE), Department of Basic Sciences and Environment, University of Copenhagen, Frederiksberg, Denmark,Faculty of Science (NAT), Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
Faculty of Science (NAT), Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
January 1, 2009
More about this publication?