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Anton Kaufmann - One of the best experts on this subject based on the ideXlab platform.
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false positive liquid chromatography tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to eu directive 2002 657 ec due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
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False‐positive liquid chromatography/tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to EU directive 2002/657/EC due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
Andreas Schurmann - One of the best experts on this subject based on the ideXlab platform.
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false positive liquid chromatography tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to eu directive 2002 657 ec due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
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False‐positive liquid chromatography/tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to EU directive 2002/657/EC due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
Pierre Lutgen - One of the best experts on this subject based on the ideXlab platform.
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It is not just artemisinin: Artemisia sp. for treating diseases including malaria and schistosomiasis
Phytochemistry Reviews, 2019Co-Authors: B. M. Gruessner, L. Cornet-vernet, M. R. Desrosiers, Michael John Towler, Pierre Lutgen, Pamela J. WeathersAbstract:Artemisia sp., especially A. annua and A. afra , have been used for centuries to treat many ailments. While artemisinin is the main therapeutically active component, emerging evidence demonstrates that the other phytochemicals in this genus are also therapeutically active. Those compounds include flavonoids, other terpenes, coumarins, and phenolic acids. Artemisia sp. phytochemicals also improve bioavailability of artemisinin and synergistically improve artemisinin therapeutic efficacy, especially when delivered as dried leaf Artemisia as a tea infusion or as powdered dry leaves in a capsule or compressed into a tablet. Here results from in vitro, and in vivo animal and human studies are summarized and critically discussed for mainly malaria, but also other diseases susceptible to artemisinin and Artemisia sp. including schistosomiasis, leishmaniasis, and trypanosomiasis.
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Artemisia annua and Artemisia afra tea infusions vs artesunate amodiaquine asaq in treating plasmodium falciparum malaria in a large scale double blind randomized clinical trial
Phytomedicine, 2019Co-Authors: Jerome Munyangi, Lucile Cornetvernet, Michel Idumbo, Pierre Lutgen, Nadege Ngombe, Jacques Bianga, Bavon Mupenda, Christian Perronne, Chen Lu, Paul LalukalaAbstract:Abstract Background and objective Prior small-scale clinical trials showed that Artemisia annua and Artemisia afra infusions, decoctions, capsules, or tablets were low cost, easy to use, and efficient in curing malaria infections. In a larger-scale trial in Kalima district, Democratic Republic of Congo, we aimed to show A. annua and/or A. afra infusions were superior or at least equivalent to artesunate-amodiaquine (ASAQ) against malaria. Methods A double blind, randomized clinical trial with 957 malaria-infected patients had two treatment arms: 472 patients for ASAQ and 471 for Artemisia (248 A. annua, 223 A. afra) remained at end of the trial. ASAQ-treated patients were treated per manufacturer posology, and Artemisia-treated patients received 1 l/d of dry leaf/twig infusions for 7 d; both arms had 28 d follow-up. Parasitemia and gametocytes were measured microscopically with results statistically compared among arms for age and gender. Results Artemisinin content of A. afra was negligible, but therapeutic responses of patients were similar to A. annua-treated patients; trophozoites cleared after 24 h, but took up to 14 d to clear in ASAQ-treated patients. D28 cure rates defined as absence of parasitemia were for pediatrics 82, 91, and 50% for A. afra, A. annua and ASAQ; while for adults cure rates were 91, 100, and 30%, respectively. Fever clearance took 48 h for ASAQ, but 24 h for Artemisia. From D14-28 no Artemisia-treated patients had microscopically detectable gametocytes, while 10 ASAQ-treated patients remained gametocyte carriers at D28. More females than males were gametocyte carriers in the ASAQ arm but were unaffected in the Artemisia arms. Hemoglobin remained constant at 11 g/dl for A. afra after D1, while for A. annua and ASAQ it decreased to 9–9.5 g/dl. Only 5.0% of Artemisia-treated patients reported adverse effects, vs. 42.8% for ASAQ. Conclusion A. annua and A. afra infusions are polytherapies with better outcomes than ASAQ against malaria. In contrast to ASAQ, both Artemisias appeared to break the cycle of malaria by eliminating gametocytes. This study merits further investigation for possible inclusion of Artemisia tea infusions as an alternative for fighting and eradicating malaria.
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Investigations of Artemisia Annua and Artemisia Sieberi Water Extracts Inhibitory Effects on Î-Hematin Formation
Medicinal and Aromatic plants, 2014Co-Authors: Mutaz Akkawi, Suhair Jaber, Qassem Abu-remeleh, Ogwang Patrick Engeu, Pierre LutgenAbstract:Malaria is the most prevalent infectious disease in the world, killing 1-2 million people each year. New drugs are urgently needed to treat drug-resistant strains of malaria. In a previous study we found that extracts from Salvia palestinia leaves inhibited the formation of β-hematin with efficiency similar to that of chloroquine. The objective of this study was to investigate the effect of other plant extracts on hemozoin formation. A comparison between the efficiency of aqueous extracts or infusions of Artemisia annua from Luxembourg and Artemisia sieberi from Palestine in inhibiting β-hematin formation was done. Although it was found that the Artemisia sieberi leaf tea infusion was less effective than that of the Artemisia annua, the stem infusion of Artemisia sieberi was found to be better than that of Artemisia annua stems. Results obtained with infusions prepared with tap or well water may be different from results obtained in the laboratory with distilled water. Artemisia annua leaf infusions prepared using salt water (0.5g salt/150ml water) had higher efficiency in inhibiting β-hematin formation than those infusions done with distilled water. Mixing equal amounts of Artemisia annua leaf and Artemisia sieberi stem water extract showed an increase in their inhibitory effect on β-hematin formation. An important finding in this investigation was that the Artemisia annua lyophilized extracts lost activity with time, which may have an impact not only on in vitro laboratory results but also on in vivo treatment efficiency obtained with old extracts. In light of this finding it might be advisable to use Artemisia annua in the form of dried leaf powder and not in the form of extracts or infusion. Stored in dry, ventilated conditions the plant keeps its properties for many years.
Patrick Butcher - One of the best experts on this subject based on the ideXlab platform.
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false positive liquid chromatography tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to eu directive 2002 657 ec due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
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False‐positive liquid chromatography/tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to EU directive 2002/657/EC due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
Claudio Cruzer - One of the best experts on this subject based on the ideXlab platform.
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false positive liquid chromatography tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to eu directive 2002 657 ec due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
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False‐positive liquid chromatography/tandem mass spectrometric confirmation of sebuthylazine residues using the identification points system according to EU directive 2002/657/EC due to a biogenic insecticide in tarragon
Rapid Communications in Mass Spectrometry, 2009Co-Authors: Andreas Schurmann, Veronika Dvorak, Claudio Cruzer, Patrick Butcher, Anton KaufmannAbstract:In pesticide residue analysis using liquid chromatography/tandem mass spectrometry (LC/MS/MS) the confirmation of a sebuthylazine finding in a tarragon (Artemisia dranunculus) sample was demonstrated to be false positive. A coeluting interfering matrix compound produced product ions in MS/MS analysis, perfectly corresponding to the multiple reaction monitoring (MRM) of two sebuthylazine transitions. Using the EU directive 2002/657/EC which regulates the confirmation of suspected positive findings would have resulted in a false-positive finding. A third LC/MS/MS transition with a deviant ion ratio and a gas chromatography (GC)/MS/MS analysis revealed the false-positive results. With optimized high resolving ultra-performance liquid chromatography (UPLC) conditions it was possible to separate spiked sebuthylazine from the interfering matrix compound. Using its exact mass and isotope ratios from LC/time-of-flight (TOF) MS measurements, the compound was identified as nepellitorine, a – not surprising – endogenous alkamide in tarragon (Arthemisia dranunculus). False-positive results, especially in heavy matrix samples such as herbs, can be dealt with by further confirmatory analysis, e.g. a third transition, GC analysis if possible or more advantageous by an orthogonal criterion like exact mass. Copyright © 2009 John Wiley & Sons, Ltd.
