Poly (hydroxybutyrate)/piroxicam microparticles prepared by emulsion/solvent evaporation: characterization and in vitro drug release

Poly (hydroxybutyrate)/piroxicam microparticles prepared by emulsion/solvent evaporation: characterization and in vitro drug release
Giovana Carolina Bazzo1; Elenara M. T. Lemos-Senna2, Alfredo Tibúrcio Nunes Pires1
1

Grupo de Estudos em Materiais Poliméricos (POLIMAT). Chemistry Department. 2Pharmaceutical Sciences Department. Federal University of Santa Catarina, Florianópolis, SC, Brasil.

Abstract – Microparticles containing piroxicam, an anti-inflammatory drug, were prepared using poly (hydroxybutyrate), by emulsion/solvent evaporation. The microparticles were evaluated in terms of morphology, encapsulation efficiency, thermal analysis and in vitro drug release. The results obtained indicate that the PHB/PXC microparticles can be considered as a promising system to control the drug delivery.

Poly (hydroxybutyrate) [PHB] is a biodegradable and biocompatible polymer with a high potential for application in drug delivery systems as microparticles. The emulsion/solvent evaporation method has been the most frequently used to prepare PHB microspheres1. In this process, the drug and the polymer are dissolved in an organic phase, which is emulsified in an aqueous phase containing a stabilizer agent, under stirring. The organic solvent diffuses into the aqueous phase and then evaporates at the water/air interface. Consequently, the polymer precipitates and the microparticles are formed2. The process parameters such as solvent type, rate of solvent removal, type and concentration of the emulsifier, drug/polymer ratio and rate of solvent removal under stirring can affect the physicochemical properties of the microparticles3. The present study aimed to prepare PHB microparticles loaded with piroxicam (PXC) as a model drug to evaluate the microparticle characteristics and the in vitro drug release. PHB/PXC microparticles were prepared by the oil-in-water emulsion/solvent evaporation technique. The polymer and the drug were dissolved in an organic solvent and then