Abstract
In this paper, dissolution characteristics of primary-particles and compressed tablets were investigated by experiments using a mathematical model. For the primary-particle, it was found that the dissolution rate increased with a decrease in the particle size. Assuming that primary-particles of size distribution were of cylindrical shape and that the dissolution occurs from the total external surface, an extended Nernst-Noyes-Whitney equation fitted to the experimental data well. As the influences of particle size and shape on thickness of a diffusion-boundary film were found to be quite low, the dissolution rate was considered to be affected by the specific surface area dominantly. Furthermore, the same model was applied to a compressed tablet and fitted to the data well. Though the rate constant obtained were not affected by the properties of primary-particles forming the tablet, it was found to increase with the apparent voidage which occupies the inter-particle volume of tablet diluent among less soluble particles. Consequently, an increase in the apparent voidage is presumed to accelerate penetration of water into the internal voids of the tablet. Thus, the dissolution going, the effective surface area inside the tablet is considered to be extended.
| Original language | English |
|---|---|
| Pages (from-to) | 146-153 |
| Number of pages | 8 |
| Journal | International Journal of Pharmaceutics |
| Volume | 310 |
| Issue number | 1-2 |
| DOIs | |
| Publication status | Published - Mar 9 2006 |
| Externally published | Yes |
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Keywords
- Active pharmaceutical ingredients
- Dissolution
- Mathematical model
- Particle shape
- Particle size
- Tablet
ASJC Scopus subject areas
- Pharmaceutical Science
Cite this
Dissolution characteristics of cylindrical particles and tablets. / Fukunaka, Tadashi; Yaegashi, Yoshiko; Nunoko, Taku; Ito, Ryusei; Golman, Boris; Shinohara, Kunio.
In: International Journal of Pharmaceutics, Vol. 310, No. 1-2, 09.03.2006, p. 146-153.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Dissolution characteristics of cylindrical particles and tablets
AU - Fukunaka, Tadashi
AU - Yaegashi, Yoshiko
AU - Nunoko, Taku
AU - Ito, Ryusei
AU - Golman, Boris
AU - Shinohara, Kunio
PY - 2006/3/9
Y1 - 2006/3/9
N2 - In this paper, dissolution characteristics of primary-particles and compressed tablets were investigated by experiments using a mathematical model. For the primary-particle, it was found that the dissolution rate increased with a decrease in the particle size. Assuming that primary-particles of size distribution were of cylindrical shape and that the dissolution occurs from the total external surface, an extended Nernst-Noyes-Whitney equation fitted to the experimental data well. As the influences of particle size and shape on thickness of a diffusion-boundary film were found to be quite low, the dissolution rate was considered to be affected by the specific surface area dominantly. Furthermore, the same model was applied to a compressed tablet and fitted to the data well. Though the rate constant obtained were not affected by the properties of primary-particles forming the tablet, it was found to increase with the apparent voidage which occupies the inter-particle volume of tablet diluent among less soluble particles. Consequently, an increase in the apparent voidage is presumed to accelerate penetration of water into the internal voids of the tablet. Thus, the dissolution going, the effective surface area inside the tablet is considered to be extended.
AB - In this paper, dissolution characteristics of primary-particles and compressed tablets were investigated by experiments using a mathematical model. For the primary-particle, it was found that the dissolution rate increased with a decrease in the particle size. Assuming that primary-particles of size distribution were of cylindrical shape and that the dissolution occurs from the total external surface, an extended Nernst-Noyes-Whitney equation fitted to the experimental data well. As the influences of particle size and shape on thickness of a diffusion-boundary film were found to be quite low, the dissolution rate was considered to be affected by the specific surface area dominantly. Furthermore, the same model was applied to a compressed tablet and fitted to the data well. Though the rate constant obtained were not affected by the properties of primary-particles forming the tablet, it was found to increase with the apparent voidage which occupies the inter-particle volume of tablet diluent among less soluble particles. Consequently, an increase in the apparent voidage is presumed to accelerate penetration of water into the internal voids of the tablet. Thus, the dissolution going, the effective surface area inside the tablet is considered to be extended.
KW - Active pharmaceutical ingredients
KW - Dissolution
KW - Mathematical model
KW - Particle shape
KW - Particle size
KW - Tablet
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UR - http://www.scopus.com/inward/citedby.url?scp=33344463207&partnerID=8YFLogxK
U2 - 10.1016/j.ijpharm.2005.12.006
DO - 10.1016/j.ijpharm.2005.12.006
M3 - Article
VL - 310
SP - 146
EP - 153
JO - International Journal of Pharmaceutics
JF - International Journal of Pharmaceutics
SN - 0378-5173
IS - 1-2
ER -