RESUMEN
The demand for a more efficient and targeted method for intranasal drug delivery has led to sophisticated device design, delivery methods, and aerosol properties. Due to the complex nasal geometry and measurement limitations, numerical modeling is an appropriate approach to simulate the airflow, aerosol dispersion, and deposition for the initial assessment of novel methodologies for better drug delivery. In this study, a CT-based, 3D-printed model of a realistic nasal airway was reconstructed, and airflow pressure, velocity, turbulent kinetic energy (TKE), and aerosol deposition patterns were simultaneously investigated. Different inhalation flowrates (5, 10, 15, 30, and 45 L/min) and aerosol sizes (1, 1.5, 2.5, 3, 6, 15, and 30 µm) were simulated using laminar and SST viscous models, with the results compared and verified by experimental data. The results revealed that from the vestibule to the nasopharynx, the pressure drop was negligible for flow rates of 5, 10, and 15 L/min, while for flow rates of 30 and 40 L/min, a considerable pressure drop was observed by approximately 14 and 10%, respectively. However, from the nasopharynx and trachea, this reduction was approximately 70%. The aerosol deposition fraction alongside the nasal cavities and upper airway showed a significant difference in pattern, dependent on particle size. More than 90% of the initiated particles were deposited in the anterior region, while just under 20% of the injected ultrafine particles were deposited in this area. The turbulent and laminar models showed slightly different values for the deposition fraction and efficiency of drug delivery for ultrafine particles (about 5%); however, the deposition pattern for ultrafine particles was very different.
RESUMEN
Nanoparticles play an important role in the molecular diagnosis, treatment, and monitoring therapeutic outcomes in various diseases. Magnetic nanoparticles are being of great interest due to their unique purposes, especially medicine, in which the application of magnetic nanoparticles is much promising. Magnetic nanoparticles have been actively investigated as the next generation of targeted drug delivery for more than three decades. This article is devoted to study on the magnetic drug targeting technique by particle tracking in the presence of a magnetic field in the carotid artery. The results showed that applying a magnetic field on the secondary branch of the external carotid artery in a pulsating non-Newtonian flow drove nanoparticles inside this sub-branch, while none of them entered that branch in the absence of magnetic field on the internal carotid artery. Wall shear stress distributions showed that high shear stress occurs near the bifurcation region, and its maximum value belongs to the junction of internal carotid artery and external carotid artery.
