Abstract Aim There is a need to bridge the data gap concerning the regional deposition of electronic nicotine delivery systems (ENDS) emissions in the airways. The present work aims to experimentally and precisely asses the aerosol regional deposition of ENDS emissions using an ex vivo model of lungs as a complementary approach to a determinist computational model and as an alternative to animal or human in vivo experiments. Methods The refill liquid of a recent tank generation ENDS was radiolabelled with sodium pertechnetate. Particle size distributions of the emissions – in mass and in radioactivity – were determined using a cascade impaction technique. The aerosol regional deposition in the airways was both calculated with a determinist computational model and experimentally assessed by gamma-camera imaging on a controlled breathing ex vivo model mimicking intrapleural depression thanks to generation of negative pressures in a sealed enclosure. Results The aerodynamic diameter of the ENDS emissions were 1.03 ± 0.11 μm and 0.87 ± 0.03 μm (mean ± SD) in radioactivity and mass, respectively. The calculations led to a thoracic deposition of 92.89 ± 0.03% and 92.74 ± 0.19% in mass and radioactivity, respectively. The experimental data of thoracic deposition obtained by quantifying the deposited aerosol with planar scintigraphy of the ex vivo model were 91 ± 4%. Conclusions The radiolabelling of the refill liquid did not affect the particle size distribution and allowed assessment of the aerosol regional deposition by two-dimensional gamma-camera imaging. When compared, no significant difference of the thoracic deposition between calculation and experimental data could be found. Moreover, data seemed to be in good accordance with previously published data. This work supports the conclusion that this preclinical respiratory model could be used to assess regional deposition of aerosol generated by an ENDS.

中文翻译：

---

使用原始离体呼吸模型进行电子烟排放的气溶胶区域沉积

摘要 目的 需要弥合有关气道中电子尼古丁传递系统 (ENDS) 排放的区域沉积的数据差距。目前的工作旨在使用离体肺模型作为确定性计算模型的补充方法和动物或人类体内实验的替代方法，通过实验和精确评估 ENDS 排放的气溶胶区域沉积。方法 用高锝酸钠放射性标记最近一代 ENDS 罐的补充液。排放物的粒度分布——质量和放射性——是使用级联撞击技术确定的。气道中的气溶胶区域沉积既使用确定性计算模型计算，又通过伽马相机成像在模拟胸膜内压抑的受控呼吸体外模型上进行实验评估，这要归功于密封外壳中产生的负压。结果 ENDS 排放物的空气动力学直径在放射性和质量方面分别为 1.03 ± 0.11 μm 和 0.87 ± 0.03 μm（平均值 ± SD）。计算导致胸部沉积物的质量和放射性分别为 92.89 ± 0.03% 和 92.74 ± 0.19%。通过对离体模型的平面闪烁扫描对沉积的气溶胶进行量化获得的胸部沉积的实验数据为 91±4%。结论 补充液的放射性标记不影响粒径分布，并允许通过二维伽马相机成像评估气溶胶区域沉积。比较时，没有发现计算和实验数据之间的胸廓沉积有显着差异。此外，数据似乎与先前公布的数据非常吻合。这项工作支持了这一结论，即该临床前呼吸模型可用于评估 ENDS 产生的气溶胶的区域沉积。