Determination of Tafenoquine in Dried Blood Spots and Plasma Using LC and Fluorescence Detection

Abstract

Background: The growing problem of parasites developing resistance to the traditional antimalarial drugs makes the development of new effective and safe drugs crucial. Tafenoquine is a new promising antimalarial drug for prophylaxis and treatment. Results: A bioanalytical method for the determination of tafenoquine in 100 µl of capillary blood applied onto sampling paper and in 100 µl of plasma has been developed and validated. The Whatman 31 ET Chr paper was treated with 0.6 mol/l tartaric acid to improve the extraction recovery and solid-phase extraction was used for cleanup procedure of the blood samples. Plasma samples were precipitated with methanol. Tafenoquine and internal standard were separated on a Zorbax SB-CN column by reversed-phase LC and detected with fluorescence detection at 262 and 470 nm. The within- and between-day variations were below 10 and 14%, respectively, over the range 50–200 nmol/l for capillary blood on sampling paper and below 6 and 10% for plasma samples. The LLOQ of the method was 50 nmol/l. Conclusion: The developed method has adequate sensitivity and is highly suitable for clinical studies in dried blood spots and plasma.

Ethical conduct of research

The authors state that they have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

Financial & competing interests disclosure

This study received financial support from Dalarna University College, the Marcus and Amelia Wallenberg foundation and the Center for Clinical Research Landstinget Dalarna. Niklas Lindegardh is part of the Wellcome Trust–Mahidol University–Oxford Tropical Medicine Research Programme (077166/Z/05/Z) supported by the Wellcome Trust of Great Britain. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

This study received financial support from Dalarna University College, the Marcus and Amelia Wallenberg foundation and the Center for Clinical Research Landstinget Dalarna. Niklas Lindegardh is part of the Wellcome Trust–Mahidol University–Oxford Tropical Medicine Research Programme (077166/Z/05/Z) supported by the Wellcome Trust of Great Britain. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.