不同装置吸嘴长度的胶囊型粉雾剂递送过程数值模拟研究

Investigation on the Delivery Numerical Simulation of a Capsule-Based Dry Powder Inhaler with Different Mouthpiece Lengths

摘要: 目的：研究胶囊型粉雾剂装置不同吸嘴长度对药物递送、沉积表现等特性的影响。方法：将针对吸入器结构及颗粒在吸入器内运动的“体外”模拟与构建仿呼吸道结构模型对气道内流场分布与颗粒运动沉积的“体内”模拟结合为一个整体，形成更趋近于真实的呼吸给药结构模型。以一种有两个不同吸嘴长度的吸入器为给药装置与一种自制载体型制剂粉末为研究对象，将吸入器、口喉和上气道组合形成呼吸给药流场计算模型，基于实验得到粒径分布设置颗粒模型，模拟探讨了在30、60和100 L/min的吸气流速下粉雾剂在吸入器内的运动情况，以及上气道模型的沉积分布规律。结果：三种流速下经长吸嘴装置递送的微细颗粒剂量均高于短吸嘴装置，且在100 L/min条件下存在显著性差异；经短吸嘴装置递送的颗粒中值粒径在30和60 L/min条件下显著性高于长吸嘴装置；在口喉区域内的颗粒沉积量经长吸嘴递送的结果高于经短吸嘴装置递送结果，而在上气道区域中经长吸嘴装置递送的颗粒沉积量高于短吸嘴装置。结论：在本研究范围内，药物颗粒沉积分数在口喉及上气道均随流速的增加而增大；长吸嘴吸入器的分散递送性能优于短吸嘴吸入器。

Abstract: Objective: To study the influence of different mouthpiece lengths on drug delivery and deposition of capsule-based dry powder inhaler. Methods: The “in vitro” simulation of inhaler structure and par-ticle movement was combined with the “in vivo” simulation of flow field distribution and particle deposition in airway to form a more realistic respiratory drug delivery structure model. In this pa-per, two inhaler devices with different mouthpiece lengths and a carrier-based formulation pow-ders were adopted as research objects. The inhaler, mouth-throat and upper airway models were combined to form airflow field model for movement of particles in inhaler and respiratory drug de-livery. And the particle model is set based on the Particle Size Distribution obtained by experiment data. The particle distribution and the dose in human lungs were discussed at flow rates of 30, 60 and 100 L/min. Results: The fine particles dose delivered by the long mouthpiece inhaler was higher than that delivered by the short mouthpiece inhaler at three flow rates, and there was a sig-nificant difference at 100 L/min. The mass median aerodynamic diameter delivered by the short mouthpiece inhaler is significantly higher than that by the long mouthpiece inhaler at 30 and 60 L/min. The particles deposition fraction in the mouth-throat delivered by the long mouthpiece in-haler is higher than that delivered by the short mouthpiece inhaler, and the particles deposition fraction delivered by the long mouth piece inhaler is higher than that delivered by the short mouthpiece inhaler in the upper airway. Conclusion: It was found that the particle deposition mass at mouth-throat and upper airway increased with the rising of the airflow rate; The dispersion per-formance of long mouthpiece device is better than that of short device.