Spray characteristics from nasal spray atomization

TL;DR

This study provides detailed experimental data on nasal spray characteristics, including droplet size and spray dynamics, to improve the realism of computational models for nasal drug delivery.

Contribution

It offers benchmark experimental data on nasal spray spray patterns and droplet sizes, aiding the development of more accurate CFD simulations.

Findings

Actuation force affects spray velocity and droplet size.

Quantitative measurements of spray cone and breakup length.

Data supports improved CFD modeling of nasal spray deposition.

Abstract

In addition to topical delivery, nasal sprays offer an alternative drug administration route to the systemic circulation, therefore avoiding the need for painful, invasive delivery techniques. Studies on the efficacy of nasal drug delivery to date have been conflicting despite its potential. In particular computational studies, e.g. Computational Fluid Dynamics (CFD), of nasal spray deposition require realistic initial spray conditions, which are lacking in the literature. This study aims to provide benchmark experimental data for CFD inputs by characterising four different types of commercially available nasal sprays used in an ENT (Ear Nose Throat) clinic. Spray characteristics were obtained via high-speed videography, while droplet size distribution (DSD) measurements were obtained with laser diffraction. Three actuation forces were evaluated, representing the use-case of an average adult, average child and the maximum force applied to the spray device. The results demonstrated that actuation force influenced spray velocity, spray duration, DSD, and breakup length. Quantitative data of Rosin-Rammler diameter distributions, spray cone angles, dispersion angles and breakup lengths were found, assisting computational models with realistic values, thereby improving future CFD studies of nasal spray drug delivery in the nasal cavity.