Design and optimization of artemether microparticles for bitter taste masking

The objective of the present investigation was to reduce the bitterness of artemether (ARM). Microparticles were prepared by the coacervation method using Eudragit E 100 (EE) as polymer and sodium hydroxide solution as nonsolvent for the polymer. A 32 full factorial design was used for optimization wherein the amount of drug (A) and polymer (B) were selected as independent variables and the bitterness score, particle size and drug release at pH, 1.2 and 6.8 were selected as dependent variables. Optimization was carried out using the desirability function. The optimized microparticles batch was characterized by FTIR and DSC. Multiple linear regression analysis revealed that reduced bitterness of ARM can be obtained by controlling the drug release of microparticles at pH 6.8 and increasing the amount of EE. The increase in the amount of polymer leads to reduction in drug release from microparticles at pH > 5 due to its insolubility and thus reduces bitterness. However, the increase in the amount of polymer results in improved dissolution, suggesting improved availability of ARM in stomach. Optimized microparticles prepared using 0.04 g of ARM and 15 mL of 1% (m/V) solution of EE showed complete bitter taste masking with improved drug release at pH 1.2.