Abstract

Summary Formulating pulmonary controlled release formulations is highly desirable when treating chronic diseases such as COPD and Asma. However, a limited number of excipients are approved for inhalation. The following study presents a promising strategy that provides a matrix for controlling the release of anionic drugs using gelatin as the core of the encapsulation process for dry powder formulations. The ionic interaction between this biodegradable polymer and the drugs allows for controlling the diffusion rate of the drug while presenting swelling properties that could help to avoid macrophage patrolling and early clearance from the lung. Even though these results are favorable, a more comprehensive study is required to understand the mechanism behind the ionic interaction between the polymer and the drug. However, this can be the start of developing a new generation of controlled release formulations. Key Message The ionic complex approach allowed for the formulation of a gelatin microcapsule capable of reducing the diffusion rate of sodium cromoglycate (SC) more efficiently. Positively charged gelatin microcapsules could interact with SC while rapidly swelling. This characteristic shows potential for increasing the residence time of the formulation by avoiding macrophage uptake.