The drug (artemisinin) was loaded onto the synthesized material (hydroxyapatite and Euclea natalensis/hydroxyapatite) by adsorption. The system was composed of artemisinin, hydroxyapatite, and 25 ± 0.1 ml of ethanol . Two different ratios of artemisinin to hydroxyapatite were used: a molar ratio of 1:2 and a mass ratio of 1:10 during which the temperature was maintained at 37 °C . A 1 mL sample was taken at predetermined intervals, and the protocol outlined in section 2.7 was followed. Subsequently, 1 mL of pure 1x PBS pH 7.4 was added to the test tube.