Formulation and In Vitro Evaluation of Alendronate Sodium/PLGA Microspheres for Applications in Bone Related Disorders

ABSTRACT: Purpose - Bisphosphonates are a group of drugs that can be used in the development of new therapies for bone disorders. Microencapsulation by solvent evaporation is a method that results in microspheres with controlled release of the drug. The purpose of the present study was to include sodium alendronate (AL) in poly (lactic-co-glycolic acid) (PLGA) microspheres with a good encapsulation rate. Furthermore it was intended to obtain a prolonged release of the drug over a period of time. Material and methods - Microspheres were prepared by water/oil/water solvent evaporation method. The microspheres were characterized by FTIR analysis using an Avatar Nicolet spectrophotometer. Both encapsulation ratio and in vitro drug release were assessed by chromatographic analysis. Results - The method chosen for sodium alendronate incorporation resulted in microspheres with a good entrapment efficiency. The in vitro drug release from PLGA/AL microspheres was maintained up to 21 days. This suggests that the microspheres had a sustained releasing tendency. Conclusion - Given the prolonged release, PLGA/AL microspheres may be used in a controlled release system with applications in bone disease treatment.