Evaluation of Stability and TLC Fingerprinting of the Artemether Component in Artemether-Lumefantrine Combination Suspension Formulations Available in Nigeria Pharmaceutical Market

Aim: Artemether is the main component of the artemisinin-based combination therapy (ACT), used in the management of malaria infection caused by Plasmodium falciparum. Hence, its stability and conformation to pharmacopeia standards are necessary for use. The study aimed to review the first-order derivative spectrophotometric method for simultaneous estimation of artemether and its derivatives in pure and combined formulations, and their stability profiles, then develop a simple, precise, and fast technique for their rapid physicochemical analysis.

Methodology: Thin-layer chromatographic (TLC) Fingerprinting principles were used in the analysis. Artemether and its derivatives were spotted on the TLC chromatograms after adding 25 mL of the suspension to a mixture of 100 mL of distilled water and 4 mL of NaOH, extracting the mixture with 60 mL of dichloromethane (DCM), drying, and sonicating the residue with 20 mL of the solvent. It was centrifuged, and the clear supernatant was spotted on the TLC plates.

Results: The color test results revealed the presence of the artemether compound in the reference standard as well as the six brands of suspensions (A, B, C, D, E, and F) utilized in the study. Artemether melting point was obtained between 86 - 89 °C; within the International Pharmacopeia specified range. The chromatograms of Artemether and derivatives showed Rf values of 0.25 (impurity A), 0.3 (artenimol impurity B), 0.35 (impurity C), 0.4 (α-artemether: impurity D), and 0.55 (artemether).

Conclusion: The devised method can be applied to the routine quality control analysis of artemether-lumefantrine suspension in addition to existing analytical techniques.