Development of taste-masking microcapsules containing azithromycin by fluid bed coating for powder for suspension and evaluation.

This research aims to develop bitter taste-masking microcapsules containing azithromycin (AZI) by a simpler and familiar method, fluid-bed coating technology, in comparison with Zithromax. Cores of microcapsules, AZI microparticles, were prepared by fluid-bed granulation, then taste-masking polymer was covered on by fluid-bed coating technique. Eudragit L100, Eudragit RL100, and ethyl cellulose in single and combined with Eudragit L100 and Eudragit E100 were used as taste-masking polymers. The obtained microcapsules were characterised by taste-masking ability, release, SEM, coating thickness, and coating efficiency. Combination of ethyl cellulose and Eudragit E100 (3:1) in coating thickness of 45.13 ± 2.12% w/w prevents AZI release from microcapsules below bitter taste threshold (1.78 ± 1.17 µg/ml). Bioavailability of powders containing AZI microcapsules and pH modulators (50 mg NaPO and 35 mg Mg(OH)) was not significantly different from the reference product (Zithromax, Pfizer, New York, NY) in the rabbit model ( > 0.05). These results support the possibility of developing a generic product containing AZI.