![]() |
![]() |
|
采用空气雾化法制备海藻酸盐微粒及其物理特性 Alginate microparticles were prepared
using an air atomization method and varying formulation and processing
conditions. Thereafter, the size and surface morphology of alginate microparticles
were characterized. The trapping efficiencies of the ketoconazole, acetaminophen,
vitamin C, and Bifidobacteria bifidum as model core materials were then
determined. The air atomization process produced free-flowing and small-size
microparticles after the freeze-drying process. The size distribution
and surface morphology varied depending on the concentration of wall-forming
materials and processing conditions. Generally, the geometric mean size
increased as the concentration of alginate and poly-1-lysine and the delivery
rate increased, but the air pressure decreased. Most of all, the ratio
of delivery rate of alginate solution and air pressure could affect the
size and surface morphology of alginate microparticles. However, the geometric
mean size of alginate poly-1-lysine microparticles reproducibly ranged
from about 80 to 130 microm. The microparticles were irregularly spherical
or elliptical. The trapping efficiencies of ketoconazole, acetaminophen,
vitamin C, and bifidobacteria were determined to be 71.5%, 60.1%, 1.6%,
and 31%, respectively, when alginate concentration (1.5%), poly-1-lysine
concentration (0.02%), air pressure (0.75 bar), delivery rate (8 ml/min),
and spraying distance (45 cm) were applied. The current microencapsulation
process using the air atomization method provides an alternative to entrapping
small molecules and macromolecules without using harmful organic solvents.
In addition, the small-size and free-flowing alginate microparticles containing
active substances can be used as an intermediate in pharmaceutical applications. [引自Drug Dev Ind Pharm 2001 Apr;27(4):309-19] |