Characterization of nasal spray aerosol fields using the extended interferometric particle imaging technique

Abstract

Nasal-drug-delivery is an effective way to improve therapeutic effect. Droplet diameter and its distribution directly impact the deposition position and bioavailability of the drug in nasal passage. In this paper, the spatial distribution of the droplet size, location and refractive index of spray are explored with extended interferometric particle imaging technique. A generalized expression of the spatial spacing of interference fringes is derived theoretically. The fringe spacing for two counter-propagating beams is the same as that for a single beam along one of the two-beam directions at the sideward scattering region, which is verified by simulation and experiment. The polystyrene microsphere and the nasal spray of physiological saline and oxytocin are tested experimentally. The relative error of microsphere size is less than 0.3 %, the refractive index accuracy of spray can reach 10−4. The method presented herein is promising for many relevant applications, such as fuel spray and nasal spray.