A dry powder for inhalation, composed of mannitol microparticles carrying calcium phosphate nanoparticles, has been developed for cardiac delivery of loaded bioactive peptide. The goal was to achieve highly efficient deposition of microparticles in the deep lung for release and translocation of drug loaded nanoparticles into blood, enabling a direct transport to the heart via the pulmonary vein. In this work, the relevant quality attributes of inhalable microparticles embedding nanoparticles were discussed. Furthermore, peptide drug release from microparticles was studied in vitro and correlated to microparticle dissolution and nanoparticle degradation.

Calcium phosphate nanoparticlesMicroparticles for pulmonary deliveryHeart diseasesMimetic peptideRelease kinetics