Preparation and Characterization of Radiopaque Chitosan Microspheres

Polymeric beads with diameter in the micrometer range find use in vanous medical applications, such as bone cements', in local delivery of drugs' and in treatment of female stress urinary incontinence.r" Medical microspheres usually consists of poly (methyl methacrylate), poly (lactic acid-eo-glycolic acid), poly (tetra fluoroethylene) or silicone rubbers. A particularly important application of microspheres relates to their use as so-called bulking agents; microspheres are injected via a syringe, usually as a suspension. The practical utility of microspheres with X-ray visibility lies in the fact that the clinician can assess possible migration in a direct manner. Polymers encapsulated with radiopacifying agents have recently been proposed as particulate emboli in endovascular embolization and for investigation of a variety of gastrointestinal disorders. Radiopaque hydrogel microspheres derived from many natural and synthetic