Abstract：
Delivering vaccines to the posterior nose has been proposed to induce mucosal immunization. However, conventional nasal devices often fail to deliver sufficient doses to the posterior nose. This study aimed to develop a new delivery protocol that can effectively deliver sprays to the caudal turbinate and nasopharynx. High-speed imaging was used to characterize the nasal spray plumes. Three-dimensional-printed transparent nasal casts were used to visualize the spray deposition within the nasal airway, as well as the subsequent liquid film formation and translocation. Influencing variables considered included the device type, delivery mode, release angle, flow rate, head position, and dose number. Apparent liquid film translocation was observed in the nasal cavity. To deliver sprays to the posterior nose, the optimal release angle was found to be 40° for unidirectional delivery and 30° for bidirectional delivery. The flow shear was the key factor that mobilized the liquid film. Both the flow shear and the head position were important in determining the translocation distance. A supine position and dual-dose application significantly improved delivery to the nasopharynx, i.e., 31% vs. 0% with an upright position and one-dose application. It is feasible to effectively deliver medications to the posterior nose by leveraging liquid film translocation for mucosal immunization.
摘要：
已经提出将疫苗递送到后鼻以诱导粘膜免疫。然而,传统的鼻装置通常无法向后鼻输送足够的剂量。这项研究旨在开发一种新的输送方案，可以有效地将喷雾剂输送到尾鼻甲和鼻咽。使用高速成像来表征鼻喷雾羽流。三维打印的透明鼻铸模用于可视化鼻气道内的喷雾沉积，以及随后的液膜形成和移位。考虑的影响变量包括设备类型，交货方式,释放角度,流量,头部位置,和剂量数。在鼻腔中观察到明显的液膜易位。为了给后鼻注射喷雾剂，发现单向递送的最佳释放角度为40°，双向递送的最佳释放角度为30°。流动剪切是动员液膜的关键因素。流动剪切和头部位置对于确定移位距离都很重要。仰卧位和双剂量应用显着改善了对鼻咽的递送，即，31%vs.0%，直立姿势和单剂量应用。通过利用液膜易位进行粘膜免疫，将药物有效地输送到后鼻是可行的。
