Preparation and characterization of poly(D,L-lactic-co-glycolic acid) microspheres containing flurbiprofen sodium

This study aimed to prepare biodegradable microspheres containing flurbiprofen sodium, a nonsteroidal anti-inflammatory drug ( NSAID), as the drug delivery system to the periodontal pocket. Microspheres were prepared from biodegradable copolymers of poly (D,L-lactic- co-glycolic acid) ( PLGA) using solvent evaporation method. The effects of the different copolymers and amounts of polyvinyl alcohol (PVA) as a dispersing agent on characteristics of the microspheres were evaluated. Although there was no correlation between microsphere size and amount of PVA, an optimum PVA concentration was essential to achieve narrower size distributions of microspheres. As the concentration of PVA increased, the drug loading of the microspheres increased. The effect of PVA on drug loading was found to be statistically significant for those microspheres prepared from PLGA 50: 50 ( p < 0.05). Regarding copolymer composition, PLGA 85: 15 provided higher drug loading into the microspheres than PLGA 50: 50 (p< 0.05). The recoveries of microspheres ( 60 - 80%) were affected neither by different PVA concentrations nor by copolymer compositions (p> 0.05). According to the first-order release rate constants of the microspheres, the microspheres of PLGA 50: 50 released the drug at the highest rate consistently, with the highest hydrophilicity of this copolymer.