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Droplet and particle size relationship and shell thickness of inhalable lactose particles during spray drying

Elversson, Jessica ; Millqvist-Fureby, Anna LU ; Alderborn, Göran and Elofsson, Ulla (2003) In Journal of Pharmaceutical Sciences 92(4). p.900-910
Abstract

To find means of controlling the size and density of particles intended for inhalation the relationship between droplet and particle size during spray drying was investigated. Lactose solutions were atomized with a two-fluid nozzle and dried in a laboratory spray drier. The effects of nozzle orifice diameter, atomization airflow and feed concentration on droplet and particle size were examined. Mass median diameter of both droplets and particles were analyzed with laser diffraction. In addition, scanning electron microscopy and transmission electron microscopy were used for studies of particle shape and morphology. It was demonstrated that nozzle orifice diameter and airflow, but not feed concentration controlled the droplet size during... (More)

To find means of controlling the size and density of particles intended for inhalation the relationship between droplet and particle size during spray drying was investigated. Lactose solutions were atomized with a two-fluid nozzle and dried in a laboratory spray drier. The effects of nozzle orifice diameter, atomization airflow and feed concentration on droplet and particle size were examined. Mass median diameter of both droplets and particles were analyzed with laser diffraction. In addition, scanning electron microscopy and transmission electron microscopy were used for studies of particle shape and morphology. It was demonstrated that nozzle orifice diameter and airflow, but not feed concentration controlled the droplet size during atomization. Increasing droplet size increased particle size but the effect was also influenced by feed concentration. Particles from solutions of a low concentration (1% w/w) were smaller than those from higher concentrations (5-20% w/w). This may be partly explained by lower yields at higher feed concentrations, but may also be related to differences in drying rate. Spray-dried lactose solutions formed hollow particles, and it was suggested that the shell thickness of the particles increased with increasing feed concentration.

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author
; ; and
publishing date
type
Contribution to journal
publication status
published
keywords
Droplet size, Laser diffraction, Particle formation, Particle size, Shell thickness, Spray drying
in
Journal of Pharmaceutical Sciences
volume
92
issue
4
pages
11 pages
publisher
Elsevier
external identifiers
  • scopus:0037381525
  • pmid:12661075
ISSN
0022-3549
DOI
10.1002/jps.10352
language
English
LU publication?
no
id
ae30b4dd-55da-4e7f-a1e6-8d35e2e4bc2a
date added to LUP
2025-04-14 17:21:20
date last changed
2025-07-08 00:13:58
@article{ae30b4dd-55da-4e7f-a1e6-8d35e2e4bc2a,
  abstract     = {{<p>To find means of controlling the size and density of particles intended for inhalation the relationship between droplet and particle size during spray drying was investigated. Lactose solutions were atomized with a two-fluid nozzle and dried in a laboratory spray drier. The effects of nozzle orifice diameter, atomization airflow and feed concentration on droplet and particle size were examined. Mass median diameter of both droplets and particles were analyzed with laser diffraction. In addition, scanning electron microscopy and transmission electron microscopy were used for studies of particle shape and morphology. It was demonstrated that nozzle orifice diameter and airflow, but not feed concentration controlled the droplet size during atomization. Increasing droplet size increased particle size but the effect was also influenced by feed concentration. Particles from solutions of a low concentration (1% w/w) were smaller than those from higher concentrations (5-20% w/w). This may be partly explained by lower yields at higher feed concentrations, but may also be related to differences in drying rate. Spray-dried lactose solutions formed hollow particles, and it was suggested that the shell thickness of the particles increased with increasing feed concentration.</p>}},
  author       = {{Elversson, Jessica and Millqvist-Fureby, Anna and Alderborn, Göran and Elofsson, Ulla}},
  issn         = {{0022-3549}},
  keywords     = {{Droplet size; Laser diffraction; Particle formation; Particle size; Shell thickness; Spray drying}},
  language     = {{eng}},
  month        = {{04}},
  number       = {{4}},
  pages        = {{900--910}},
  publisher    = {{Elsevier}},
  series       = {{Journal of Pharmaceutical Sciences}},
  title        = {{Droplet and particle size relationship and shell thickness of inhalable lactose particles during spray drying}},
  url          = {{http://dx.doi.org/10.1002/jps.10352}},
  doi          = {{10.1002/jps.10352}},
  volume       = {{92}},
  year         = {{2003}},
}