Polymer-lipid microparticles for pulmonary delivery.

Toward engineering approaches that are designed to optimize the particle size, morphology, and mucoadhesion behavior of the particulate component of inhaler formulations, this paper presents the preparation, physicochemical characterization, and preliminary in vitro evaluation of multicomponent polymer-lipid systems that are based on "spray-drying engineered" alpha-lactose monohydrate microparticles. The formulations combine an active (budesonide) with a lung surfactant (dipalmitoylphosphatidylcholine) and with materials that are known for their desirable effects on morphology (polyvinyl alcohol), aerosolization (L-leucine), and mucoadhesion (chitosan). The effect of the composition of formulations on the morphology, distribution, and in vitro mucoadhesion profiles is presented along with "Calu-3 cell monolayers" data that indicate good cytocompatibility and also with simulated-lung-fluid data that are consistent with the therapeutically useful release of budesonide.