Manufacture andIn-VitroAssessment of Bromsulphthalein and Phenolphthalein Loaded Polyester Microspheres

Abstract
Poly(lactic acid) and Poly(glycolic acid) microspheres were manufactured by a solvent evaporation and precipitation technique respectively. Particle size and image analysis of the microspheres were performed to establish their morphology. Phenolphthalein and bromsulphthalein, were incorporated in the polymeric microspheres. The release of phenolphthalein in glycine buffer pH 10.8 and bromsulphthalein in phosphate buffer pH 7.4 at 25°C was delayed compared with dye alone. This data has been correlated with the in-vivo performance of the polymeric matrix dye delivery systems.