A 3D printed human upper respiratory tract model for particulate deposition profiling.

Area of Science:

• Biomedical Engineering
• Pharmacology
• Respiratory Medicine

Background:

• Pulmonary drug delivery is crucial for asthma and COPD management, offering advantages over oral administration.
• Accurate assessment of drug deposition in the respiratory tract is vital for evaluating inhalation device efficacy.
• Current in vitro methods like cascade impactors do not fully replicate in vivo human respiratory deposition patterns.

Purpose of the Study:

• To develop and validate a 3D-printed in vitro model of the human upper respiratory tract.
• To assess the model's accuracy in predicting drug deposition patterns.
• To investigate the influence of spacers and airflow rates on drug deposition.

Main Methods:

• Fabrication of a human upper respiratory tract model using 3D printing technology.
• Characterization of the model for dimensional accuracy, surface finish, and air leakage.
• In vitro testing of salbutamol sulphate deposition using a metered dose inhaler with and without a spacer at various airflow rates (15 L/min and 35 L/min).

Main Results:

• The 3D-printed model demonstrated high dimensional accuracy and minimal air leakage.
• Drug deposition patterns at 15 L/min with a spacer closely matched published in vivo radiological study results.
• Deposition patterns at 35 L/min showed comparability with other human in vivo studies.

Conclusions:

• The developed 3D-printed in vitro respiratory tract model offers a reliable tool for predicting in vivo drug deposition.
• This model exhibits a reasonable in vitro-in vivo correlation, supporting its use in inhalation device assessment.
• The model holds potential for advancing personalized medicine approaches in respiratory conditions and special patient populations.