Inthavong Kiao, Fung Man Chiu, Yang William, Tu Jiyuan
1 School of Aerospace, Mechanical and Manufacturing Engineering, RMIT University , Bundoora, Victoria, Australia .
J Aerosol Med Pulm Drug Deliv. 2015 Feb;28(1):59-67. doi: 10.1089/jamp.2013.1093. Epub 2014 Jun 10.
To evaluate the deposition efficiency of spray droplets in a nasal cavity produced from a spray device, it is important to determine droplet size distribution, velocity, and its dispersion during atomization. Due to the limiting geometric dimensions of the nasal cavity airway, the spray plume cannot develop to its full size inside the nasal vestibule to penetrate the nasal valve region for effective drug deposition.
Particle/droplet image analysis was used to determine local mean droplet sizes at eight regions within the spray plume under different actuation pressures that represent typical hand operation from pediatric to adult patients.
The results showed that higher actuation pressure produces smaller droplets in the atomization. Stronger actuation pressure typical of adult users produces a longer period of the fully atomized spray stage, despite a shorter overall spray duration. This produces finer droplets when compared with the data obtained by weaker actuation pressure, typical of pediatric users.
The experimental technique presented is able to capture a more complete representation of the droplet size distribution and the atomization process during an actuation. The measured droplet size distribution produced can be related to the empirically defined deposition efficiency curve of the nasal cavity, allowing a prediction of the likely deposition.
为评估喷雾装置产生的喷雾液滴在鼻腔内的沉积效率，确定雾化过程中的液滴尺寸分布、速度及其扩散情况非常重要。由于鼻腔气道的几何尺寸有限，喷雾羽流在鼻前庭内无法充分展开，难以穿透鼻瓣区实现有效的药物沉积。
采用颗粒/液滴图像分析方法，在不同驱动压力下测定喷雾羽流内八个区域的局部平均液滴尺寸，这些压力代表了从儿科到成人患者的典型手动操作。
结果表明，较高的驱动压力在雾化过程中产生较小的液滴。成人使用者典型的较强驱动压力会产生较长时间的完全雾化喷雾阶段，尽管总喷雾持续时间较短。与儿科使用者典型的较弱驱动压力所获得的数据相比，这会产生更细小的液滴。
所提出的实验技术能够更完整地呈现驱动过程中的液滴尺寸分布和雾化过程。所测得的液滴尺寸分布可与鼻腔经验定义的沉积效率曲线相关联，从而预测可能的沉积情况。
