| Autor: |
Morita, Takahiro, Horikiri, Yuji, Yamahara, Hiroshi, Suzuki, Takehiko, Yoshino, Hiroyuki |
| Zdroj: |
Pharmaceutical Research; Nov2000, Vol. 17 Issue 11, p1367-1373, 7p |
| Abstrakt: |
Purpose. Preparation of spherical fine protein microparticles by the lyophilization of a protein-poly(ethylene glycol) (PEG) aqueous mixture was investigated. The main objective was to establish a method for preparing protein microparticles suitable for pharmaceutical production. Methods. Aqueous solutions containing bovine serum albumin (BSA) and PEG at various mixing ratios were freeze-dried. The lyophilizates were dispersed in methylene chloride and subjected to particle size analysis. Analogous studies were performed using several model proteins. A phase diagram of the PEG-BSA aqueous system was obtained by the titration method. Results. The particle size of BSA decreased as the PEG-BSA ratio increased. A bending point was observed in this relationship, at which the PEG-BSA ratio coincided with that of the critical point on the phase diagram of the PEG-BSA system. These results were explained by the freezing-induced condensation, followed by phase separation in the PEG-BSA system. Conclusions. Spherical fine protein microparticles were successfully obtained at high yield and without any activity loss under optimum conditions. This new technology could be applicable to proteins with a wide range of molecular weights, and is expected to be developed for dry powder inhalations or long-term sustained release microsphere formulations. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Full text from SpringerLink