INFLUENCE
OF ACCELERATED STORAGE CONDITIONS ON THE STABILITY OF VANCOMYCIN-LOADED
POLY (D,L-LACTIDE-CO-GLYCOLIDE) MICROSPHERES
Burcu Sayın*, Sema ÇALIŞ*o
* Hacettepe University, Faculty of Pharmacy, Department
of Pharmaceutical Thechnology, 06100 Sıhhiye, Ankara, TURKEY.
oCorresponding Author
Summary
Poly(lactide-co-glycolide) (PLGA) polymers are widely used
synthetic biodegradable materials, especially for controlled
delivery of drugs, but conditions affecting degradation
mechanisms of these polymers have not been studied in detail
in microsphere systems. In this study, the effect of temperature
and humidity on the stability and physicochemical characteristics
of vancomycin loaded PLGA (75:25) (MW 136,000) microspheres
was investigated. The changes in the surface morphology,
drug content and particle size distribution of the microspheres
prepared by the o/w type emulsion solvent evaporation method
were examined and evaluated after a three-month storage
under accelerated conditions (40 ± 2°C, 75 ±
5% relative humidity). At the end of this period, it was
observed that the spherical shape of the microspheres was
completely deformed and that polymer particles had formed
on the surface, the particle size of the microspheres had
increased from 77 µm to 810 µm, and almost 10%
of vancomycin content was determined to be lost.
Key Words :
PLGA, stability, microspheres, temperature,
humidity, accelerated conditions.
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