Optimizing Aerosolization Using Computational Fluid Dynamics in a Pediatric Air-Jet Dry Powder Inhaler.
AAPS PharmSciTech
; 20(8): 329, 2019 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-31676991
ABSTRACT
The objective of this study was to optimize the performance of a high-efficiency pediatric inhaler, referred to as the pediatric air-jet DPI, using computational fluid dynamics (CFD) simulations with supporting experimental analysis of aerosol formation. The pediatric air-jet DPI forms an internal flow pathway consisting of an inlet jet of high-speed air, capsule chamber containing a powder formulation, and outlet orifice. Instead of simulating full breakup of the powder bed to an aerosol in this complex flow system, which is computationally expensive, flow-field-based dispersion parameters were sought that correlated with experimentally determined aerosolization metrics. For the pediatric air-jet DPI configuration that was considered, mass median aerodynamic diameter (MMAD) directly correlated with input turbulent kinetic energy normalized by actuation pressure and flow kinetic energy. Emitted dose (ED) correlated best with input flow rate multiplied by the ratio of capillary diameters. Based on these dispersion parameters, an automated CFD process was used over multiple iterations of over 100 designs to identify optimal inlet and outlet capillary diameters, which affected system performance in complex and unexpected ways. Experimental verification of the optimized designs indicated an MMAD < 1.6 µm and an ED > 90% of loaded dose. While extrathoracic depositional loss will be determined in future studies, at an operating flow rate of 15 L/min, it is expected that pediatric mouth-throat or even nose-throat aerosol deposition fractions will be below 10% and potentially less than 5% representing a significant improvement in the delivery efficiency of dry powder pharmaceutical aerosols to children.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sistemas de Liberação de Medicamentos
/
Desenho de Equipamento
/
Inaladores de Pó Seco
/
Hidrodinâmica
Tipo de estudo:
Prognostic_studies
Limite:
Child
/
Humans
Idioma:
En
Revista:
AAPS PharmSciTech
Assunto da revista:
FARMACOLOGIA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos