Abstract

PREPARATION AND EVALUATION OF ARTEMISININFREEZEDRIED POWDERS WITH ENHANCED BIOAVAILABILITY

Gamal Osman Elhassan*, Yuen Kah Hay, Wong Jia Woei, Jiyauddin Khan, Khalid Omer Alfarouk and Jawed Akhter

Abstract

Artemisinin (ART) is an oral antimalarial agent with poor aqueoussolubilityand low oral bioavailability. The present study describes thepreparation of artemisinin freeze dried powder using different carriers(polyvinyl pyrolidone K-25 (PVP K-25), hydroxyl propyl cellulose(HPC) and dextrin) designed to enhance the solubility of artemisinin.and hence oral bioavailability of artemisinin, a poorly water-solubleDrug.,Artemisinin freeze dried powders were prepared by dissolvingdifferent carriers (PVP K-25, HPC and dextrin) in water followed bythe addition of artemisinin at a ratio of 1:4. The resultant products wereevaluated using the solubility and dissolution studies, differentialscanning calorimeter (DSC) and scanning electron microscopic (SEM).Relative bioavailability studies were conducted in Sprague-Dawely rats using the optimizedformulation against the reference suspension. The in vitro studies showed that the aqueoussolubility of artemisinin has increased significantly for the preparation containingartemisinin-dextrin at a ratio of 1:4. Further, the effect of incorporation of different cocarriers(citric acid or mannitol) to artemisinin-dextrin freeze-dried powder at different ratiowas evaluated. There was a significant increase in the solubility and dissolution rate ofartemisinin was obtained with the artemisinin-dextrin-citric acid freeze-dried powder at aratio of 1:3:1. In addition, there was statistically significant increase in the oral bioavailabilityof freeze dried artemisinin-dextrin-citric acid mixture compared to reference suspension. The rate and extent of absorption were enhanced by 3.4 folds. In conclusion freeze, dried product of artemisinin was able to increase the solubility, dissolution and therefore, the oral bioavailability.

Keywords: Artemisinin, freeze dried, solubility, dissolution, oral bioavailability.