title: Carbon dioxide emulsion assisted loading of polymer microspheres toward sustained release materials.
abstract: An organic solvent-free method for encapsulating progesterone at high loadings within micron-sized inert latex polymer beads is reported. This approach makes use of a polymeric surfactant to emulsify carbon dioxide into an aqueous latex suspension. In this way, preformed approximately 4 microm polystyrene (PS) microparticles surface-grafted with poly(N-vinylpyrrolidone) (PVP) were plasticized and swollen followed by rapid partitioning of progesterone into the polymer matrix. The as-prepared polystyrene beads incorporated over 10% progesterone by weight while maintaining their initial size and morphological uniformity. Dissolution experiments were also carried out to obtain the release profile of progesterone entrapped within the PVP/PS particles.
authors.forename: Gary A
authors.initials: GA
authors.lastname: Baker
authors.forename: Mary L
authors.initials: ML
authors.lastname: Campbell
authors.forename: Matthew Z
authors.initials: MZ
authors.lastname: Yates
authors.forename: T Mark
authors.initials: TM
authors.lastname: McCleskey
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D008863:Microspheres; D049329:Nanostructures; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D011374:Progesterone / Q000737:chemistry*; D011759:Pyrrolidines / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry
chemical_list: D011137:Polystyrenes; D011145:Polyvinyls; D011759:Pyrrolidines; D012997:Solvents; D013501:Surface-Active Agents; C505150:poly(N-vinylpyrrolidine); D002245:Carbon Dioxide; D011374:Progesterone