Majoral Caroline, Coates Allan L, Le Pape Alain, Vecellio Laurent
INSERM, Research Center for Respiratory Diseases, Tours, France.
Université de Tours, Tours, France.
Front Bioeng Biotechnol. 2020 Nov 13;8:589782. doi: 10.3389/fbioe.2020.589782. eCollection 2020.
Aerosol sizing is generally measured at ambient air but human airways have different temperature (37°C) and relative humidity (100%) which can affect particle size in airways and consequently deposition prediction. This work aimed to develop and evaluate a new method using cascade impactor to measure particle size at human physiological temperature and humidity (HPTH) taking into account ambient air conditions. A heated and humidified trachea was built and a cascade impactor was heated to 37°C and humidified inside. Four medical aerosols [jet nebulizer, mesh nebulizer, Presurized Metered Dose Inhaler (pMDI), and Dry Powder Inhaler (DPI)] under ambient conditions and at HPTH were tested. MMAD was lower at HPTH for the two nebulizers; it was similar at ambient conditions and HPTH for pMDI, and the mass of particles smaller than 5 μm decreased for DPI at HPTH (51.9 vs. 82.8 μg/puff). In conclusion, we developed a new method to measure particle size at HPTH affecting deposition prediction with relevance. studies are required to evaluate the interest of this new model to improve the precision of deposition prediction.
气溶胶粒径通常在环境空气中测量，但人体气道具有不同的温度（37°C）和相对湿度（100%），这会影响气道中的颗粒大小，进而影响沉积预测。本研究旨在开发并评估一种新方法，该方法使用级联撞击器在考虑环境空气条件的情况下，测量人体生理温度和湿度（HPTH）下的颗粒大小。构建了一个加热加湿的气管模型，并将级联撞击器加热到37°C并在内部进行加湿处理。对四种医用气雾剂[喷射雾化器、网状雾化器、压力定量吸入器（pMDI）和干粉吸入器（DPI）]在环境条件和HPTH条件下进行了测试。对于两种雾化器，HPTH条件下的质量中值空气动力学直径（MMAD）较低；对于pMDI，其在环境条件和HPTH条件下相似；对于DPI，HPTH条件下小于5μm的颗粒质量减少（51.9对82.8μg/吸）。总之，我们开发了一种新方法来测量HPTH条件下的颗粒大小，该方法对沉积预测有影响且具有相关性。需要开展研究以评估这种新模型在提高沉积预测精度方面的价值。
