An Efficient RP-HPLC Method for the Simultaneous Quantitative Determination of Artemether and Lumefantrine In Human Plasma by using Dad Detection

Artemether-lumefantrine (ART-LUME) off late has become the first-line treatment for uncomplicated malaria in many Sub-Saharan Africa, Asia and America. Vigorous monitoring of the therapeutic efficacy of this treatment is needed. This requires high-quality studies following standard protocols; ideally, such studies should incorporate measurement of drug levels in human plasma in biological matrices. A specific and reliable isocratic mode RP-HPLC method has been developed and validated for simultaneous determination of artemether (ART) in combination with lumefantrine (LUME) in human plasma using diode array detector (DAD) at 238 nm. The analyte was separated on NUCLEOSIC-CN Cyano coloumn (150 mm × 4.6 mm, particle size 5 μm) using a mobile phase consisting of acetonitrile and acidic buffer (adjusted to pH 2.5 with H3PO4 ­– 2 %) in the ratio of 37: 63 v/v and flow rate was 1 ml/min. The method is linear over a range of 100-1600 µg/ml (r2 ≥ 0.999) and 1-16µg/ml (r2 ≥0.998) for the assay of ART and LUME respectively. Itraconazole (ITZ) (10µg/ml) was used as internal standard. The retention times of ART and LUME was found to be 4.3 min and 14.3 respectively. Mean extraction recovery for ART and LUME were 87.3 % and 89.1 %, respectively. Inter and intraday coefficients of variation for ART and LUME were ≤ 10%. The lower limits of quantification for ART and LUME were 0.22 and 0.66 μg/ml, respectively. The results of the study showed that the proposed RP-HPLC validated method described is efficient and has the necessary accuracy and precision for the rapid quantitative simultaneous determination of ART and LUME in human plasma and is thus highly suitable for use in pharmacokinetic /bioavailability/bioequivalence studies in healthy human subjects.