Targeted Delivery of Inhalation Medicine using Magnetic Particles

The pulmonary route presents an attractive delivery pathway for topical treatment of lung diseases. While significant progress has been achieved in understanding the physical underpinnings of aerosol deposition in the lungs, our ability to target or confine the deposition of inhaled particles to specific lung regions remains meagre. It has been hypothesized that by coupling magnetic particles to inhaled therapeutics, the ability to target points in the lungs (e.g. tumor targeting), can be substantially improved. Although this method has been proven feasible in seminal in vivo rodent studies, there are still great technological gaps preventing successful treatment in humans. In this work we explore the transport phenomena of magnetic particle inhalation, and identify the main challenges preventing successful magnetic drug targeting in humans. In silico Computational fluid dynamics simulations coupled with a discrete element method solver (CFD-DEM) are used in anatomically-inspired conductive and acinar airway geometries, to resolve the motion of magnetically loaded micro-carriers. Subsequently, an in vitro system is designed and constructed, consisting of a smart inhaler coupled with a custom-made ventilation machine, and a 3D printed airway geometry. Using laser sheet illumination, our experiments track the motion of the aerosol bolus and subsequent deposition within the vicinity of the magnet, quantified via fluorescence microscopy. Our inhalation platform allows for the first time to target aerosols to deep lung tumors and may pave the way for improved treatment outcomes and reduced side effects in lung cancer patients.