Mathematical models of particle deposition in the human respiratory tract

Heyder, J.; Rudolf, G.

doi:10.1016/0021-8502(84)90007-7

Cited by 63 publications

(29 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Numerous mathematical models for calculating particle deposition within the respiratory tract have been developed using data representing these parameters (Findeisen, 1935;Morrow et al, 1966;Taulbee and Yu, 1975;Yeh and Schum, 1980;Heyder and Rudolf, 1984;International Commission on Radiological Protection, 1994; National Council on Radiation Protection and Measurements, 1997;Rijksinstituut Voor Volksgezondheid en Milieu, 1999a, b). Some of these models have been extensively used for risk assessment purposes.…”

Section: Tion; Lung Castsmentioning

confidence: 99%

Dosimetry implications of upper tracheobronchial airway anatomy in two mouse varieties

Oldham

Phalen

2002

Anat. Rec.

View full text Add to dashboard Cite

Strain-and variety-related differences in responses of mice have been reported for a variety of inhaled particulate and gaseous materials. It is important to understand the potential contributions to such responses of differences in delivered doses to the respiratory tract as well as differences in biochemical processes. Deposition doses of inhaled particles are influenced by several factors, including airway anatomy, ventilation, and particle characteristics. Tracheobronchial airway morphometry for airway generations 1-6 of the BALB/c mouse was generated using replica lung casts prepared in situ. Measurements were performed on two groups: control and ovalbumin-sensitized male BALB/c mice. These measurements were compared with previously published airway morphometry of male B6C3F 1 mice. Sensitization did not significantly change measured airway dimensions in the BALB/c mouse. However, the two mouse varieties had significant differences in airway anatomy. The differences found in airway anatomy between mouse varieties correlated with differences in body length and chest circumference. Particle deposition predictions for both varieties of mice were performed for unit density spherical particles from 0.1 to 10 m in diameter at two ventilation rates using a published aerosol dosimetry computer code. Particle deposition in the proximal tracheobronchial tree ranged up to 3 times greater for the BALB/c mouse for a 2 m particle diameter and high ventilation rate. These differences in predicted particle deposition suggest that observed strain and variety differences in response to inhaled particulate matter may be in part due to differences in delivered doses to the respiratory tract. Anat Rec 268: 59 -65, 2002.

show abstract

Section: Tion; Lung Castsmentioning

confidence: 99%

Dosimetry implications of upper tracheobronchial airway anatomy in two mouse varieties

Oldham

Phalen

2002

Anat. Rec.

View full text Add to dashboard Cite

show abstract

“…Various modelling approaches have been applied for analysing the aerosol deposition performance within the pulmonary system [1,2], for example semi-empirical [3], symmetric generation [4], trumpet [5], asymmetric multiple path modes [6], stochastic, asymmetric generation [2] and computational fluid dynamics (CFD) models [7]. Unfortunately, the results of these models vary primarily due to different lung inlet morphometric conditions such as breathing periods, pressure gradients and mathematical modelling techniques.…”

Section: Introductionmentioning

confidence: 99%

Importance of Physical and Physiological Parameters in Simulated Particle Transport in the Alveolar Zone of the Human Lung

Çiloğlu

Athari²,

Bölükbaşi

et al. 2017

Applied Sciences

View full text Add to dashboard Cite

Abstract:The trajectory and deposition efficiency of micron-sized (1-5 µm) particles, inhaled into the pulmonary system, are accurately determined with the aid of a newly developed model and modified simulation techniques. This alveolar model, which has a simple but physiologically appropriate geometry, and the utilized fluid structure interaction (FSI) methods permit the precise simulation of tissue wall deformation and particle fluid interactions. The relation between tissue movement and airflow in the alveolated duct is solved by a two-way fluid structure interaction simulation technique, using ANSYS Workbench (Release 16.0, ANSYS INC., Pittsburgh, PA, USA, 2015). The dynamic transport of particles and their deposition are investigated as a function of aerodynamic particle size, tissue visco-elasticity, tidal breathing period, gravity orientation and particle-fluid interactions. It is found that the fluid flows and streamlines differ between the present flexible model and rigid models, and the two-way coupling particle trajectories vary relative to one-way particle coupling. In addition, the results indicate that modelling the two-way coupling particle system is important because the two-way discrete phase method (DPM) approach despite its complexity provides more extensive particle interactions and is more reliable than transport results from the one-way DPM approach. The substantial difference between the results of the two approaches is likely due to particle-fluid interactions, which re-suspend the sediment particles in the airway stream and hence pass from the current generation.

show abstract

“…Thus, deposition of drug-bearing NPs in the lungs may offer the potential for sustained drug action and release throughout the lumen of the lungs, not only in the deep lung or alveolar region, where macrophage clearance occurs. However, the utility of NPs for drug release is severely limited because of their low inertia, which causes them to be predominantly exhaled from the lungs after inspiration (10,11). Moreover, their small size leads to particleparticle aggregation, making physical handling of NPs difficult in liquid and dry powder forms; this is a common practical problem that must be overcome before using NPs for oral drug delivery (12,13).…”

mentioning

confidence: 99%

Trojan particles: Large porous carriers of nanoparticles for drug delivery

Tsapis

Bennett²,

Jackson³

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

492

346

View full text Add to dashboard Cite

We have combined the drug release and delivery potential of nanoparticle (NP) systems with the ease of flow, processing, and aerosolization potential of large porous particle (LPP) systems by spray drying solutions of polymeric and nonpolymeric NPs into extremely thin-walled macroscale structures. These hybrid LPPs exhibit much better flow and aerosolization properties than the NPs; yet, unlike the LPPs, which dissolve in physiological conditions to produce molecular constituents, the hybrid LPPs dissolve to produce NPs, with the drug release and delivery advantages associated with NP delivery systems. Formation of the large porous NP (LPNP) aggregates occurs via a spray-drying process that ensures the drying time of the sprayed droplet is sufficiently shorter than the characteristic time for redistribution of NPs by diffusion within the drying droplet, implying a local Peclet number much greater than unity. Additional control over LPNPs physical characteristics is achieved by adding other components to the spray-dried solutions, including sugars, lipids, polymers, and proteins. The ability to produce LPNPs appears to be largely independent of molecular component type as well as the size or chemical nature of the NPs. L arge porous particles (LPPs), characterized by geometric sizes larger than 5 m and mass densities around 0.1 g͞cm 3 or less, have achieved recent popularity as carriers of drugs to the lungs for local and systemic applications (1, 2). A principal advantage of LPPs relative to conventional inhaled therapeutic aerosol particles is their aerosolization efficiency (3, 4); in addition, LPPs possess the potential for avoidance of alveolar macrophage clearance (5-7), enabling sustained drug release in the lungs (8).Particles with geometric diameters less than a few hundred nanometers (9) represent an even more tenacious resident of the lungs. Once deposited, nanoparticles (NPs) or ''ultrafine'' particles often remain in the lung lining fluid until dissolution (assuming they are soluble), escaping both phagocytic and mucociliary clearance mechanisms (5-8). Thus, deposition of drug-bearing NPs in the lungs may offer the potential for sustained drug action and release throughout the lumen of the lungs, not only in the deep lung or alveolar region, where macrophage clearance occurs. However, the utility of NPs for drug release is severely limited because of their low inertia, which causes them to be predominantly exhaled from the lungs after inspiration (10, 11). Moreover, their small size leads to particleparticle aggregation, making physical handling of NPs difficult in liquid and dry powder forms; this is a common practical problem that must be overcome before using NPs for oral drug delivery (12, 13). As a result of these limitations, NPs are not presently being explored commercially or clinically as vehicles for drug delivery in the lungs.We have developed a form of particle for drug delivery that combines the advantages of LPPs and NPs while avoiding their limitations. We use spray drying (14) to form...

show abstract

Mathematical models of particle deposition in the human respiratory tract

Cited by 63 publications

References 35 publications

Dosimetry implications of upper tracheobronchial airway anatomy in two mouse varieties

Dosimetry implications of upper tracheobronchial airway anatomy in two mouse varieties

Importance of Physical and Physiological Parameters in Simulated Particle Transport in the Alveolar Zone of the Human Lung

Trojan particles: Large porous carriers of nanoparticles for drug delivery

Contact Info

Product

Resources

About