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Pharmaceutical Research

, Volume 27, Issue 9, pp 1800–1811 | Cite as

Evaluation of Enhanced Condensational Growth (ECG) for Controlled Respiratory Drug Delivery in a Mouth-Throat and Upper Tracheobronchial Model

  • Michael Hindle
  • P. Worth Longest
Research Paper

ABSTRACT

Purpose

The objective of this study is to evaluate the effects of enhanced condensational growth (ECG), as a novel inhalation drug delivery method, on nano-aerosol deposition in a mouth-throat (MT) and upper tracheobronchial (TB) model using in vitro experiments and computational fluid dynamics (CFD) simulations.

Methods

Separate streams of nebulized nano-aerosols and saturated humidified air (39°C—ECG; 25°C—control) were combined as they were introduced into a realistic MT-TB geometry. Aerosol deposition was determined in the MT, generations G0-G2 (trachea—lobar bronchi) and G3-G5 and compared to CFD simulations.

Results

Using ECG conditions, deposition of 560 and 900 nm aerosols was low in the MT region of the MT-TB model. Aerosol drug deposition in the G0-G2 and G3-G5 regions increased due to enhanced condensational growth compared to control. CFD-predicted depositions were generally in good agreement with the experimental values.

Conclusions

The ECG platform appears to offer an effective method of delivering nano-aerosols through the extrathoracic region, with minimal deposition, to the tracheobronchial airways and beyond. Aerosol deposition is then facilitated as enhanced condensational growth increases particle size. Future studies will investigate the effects of physio-chemical drug properties and realistic inhalation profiles on ECG growth characteristics.

KEY WORDS

computational fluid dynamics condensational growth in vitro aerosol deposition nano-aerosol drug delivery respiratory drug delivery 

ABBREVIATIONS

CFD

computational fluid dynamics

DPI

dry powder inhaler

ECG

enhanced condensational growth

G

generation

MDI

metered dose inhaler

MT

mouth-throat

SD

standard deviation

TB

tracheobronchial

Notes

ACKNOWLEDGEMENTS

This study was supported by Award Number R21HL094991 from the National Heart, Lung, And Blood Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Heart, Lung, And Blood Institute or the National Institutes of Health.

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of PharmaceuticsVirginia Commonwealth UniversityRichmondUSA
  2. 2.Department of Mechanical EngineeringVirginia Commonwealth UniversityRichmondUSA

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