abstract |
The polyurethane microparticles are derived from structural units comprising a poly (alkylene oxide) moiety, a caprolactone moiety and a urethane moiety. The microparticles contain an active substance and can have a particle size of 0.1 to 100 microns. Microparticles for injection have a particle size of 15 to 80 microns, microparticles for use as an aerosol are 1 to 3 microns, and particles for intraocular use have a particle size of 0.02 to 2 microns. Dispersibility is in the range of 1-3. |