Aerodynamic performance of tailored microparticles as carriers in dry powder inhaler formulations made by multi-focus multi-photon 3D laser printing

The influence of carrier particle’s geometry on its performance as a drug carrier remains a challenge. Here, tailored and additively manufactured microparticles as carriers in interactive powder mixtures for inhalation are investigated. The crucial step of production of 50 µm sized complex microparticles is accomplished by multi-photon 3D laser printing. The produced powder is mixed with a model drug. Four different potential carrier geometries are printed, as well as three different surface roughnesses, created by altering the printing settings. All interactive powder mixtures are tested for drug homogeneity and aerodynamic performance, scouting for the carrier geometry with the highest drug fine particle fraction below 5 µm, i.e., the respirable fraction. A significant difference in the performance of the geometries is found, with one geometry, i.e., the Pharmacone, showing the best results. The surface roughness has no significant influence on the fine particle fraction during the aerodynamic assessment.