Preparation, characterization and antimalarial activity of dihydroartemisinin / β-cyclodextrin spray-dried powder

In this study a factorial design was used to optimize process conditions to produce spray-dried powder of dihydroartemisinin (DHA) with β-cyclodextrin (β-CD). Predicted conditions for maximum yield and minimum residual moisture were as follows: inlet temperature; 120 °C, aspirator setting; 100%, feed rate; 25%, and molar ratio of DHA:β-CD; 1:2. The higher percent inclusion yield was obtained in the spray-dried powder with lower molar ratio of DHA:β-CD. DHA existed in amorphous state in the spray-dried powder with 1:2 M ratio of DHA:β-CD whereas it was in crystalline state in the spray-dried powder with 2:1 M ratio of DHA:β-CD. The inclusion complex formation between DHA and β-CD was revealed by FTIR study. The spray-dried powder of DHA with β-CD showed dramatically enhanced dissolution rate with unchanged antimalarial activity. Moreover, it was chemically and physically stable at 30 °C, 75%RH for 3 months after storage.