Abstract
Purpose. This study was conducted to evaluate the effect of formulation variables and breathing patterns on aerosol distribution in the nasal cavity. Methods. Placebo nasal spray formulations containing 0.25% w/v Avicel CL611 (viscosity = 4 cP) and 2% w/v methylcellulose (MC; viscosity = 18.2 cP) were radiolabeled with 99mTechnicium. Following spraying into a silicone nose model, through which air was drawn at one of three constant rates (0, 10, and 20 L/min) or one of two breathing profiles (representing fast and slow inhalations), aerosol deposition in the model was quantified by gamma scintigraphy. Regional deposition was expressed as horizontal[inner, middle (h), outer] and vertical distribution [upper, middle (v), lower] in the nose model. Results. Compared to 2% MC, Avicel CL611 significantly increased aerosol deposition in the middle (h) region of the nasal cavity under all breathing conditions, and in the inner region at 0 and 20 L/min and with a slow inhalation. The different breathing rates showed no effect on deposition of 2% MC. However, 10 L/min significantly increased the upper deposition of Avicel compared to 0 and 20 L/min. Conclusions. Nasal sprays with a low viscosity provided greater surface coverage of the nasal mucosa than higher viscosity formulations. Changes in breathing profiles did not affect aerosol deposition in this nose model.
Original language | English (US) |
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Pages (from-to) | 1871-1878 |
Number of pages | 8 |
Journal | Pharmaceutical Research |
Volume | 22 |
Issue number | 11 |
DOIs | |
State | Published - Nov 2005 |
Keywords
- Breathing pattern
- Deposition
- Formulation
- Gamma scintigraphy
- Nasal spray
ASJC Scopus subject areas
- Biotechnology
- Molecular Medicine
- Pharmacology
- Pharmaceutical Science
- Organic Chemistry
- Pharmacology (medical)