| 摘要 |
<p>Provided are a method for preventing the formation of coarse particles in the process of freeze-drying an aqueous suspension of fine polylactic acid particles, and a method for producing polylactic acid particles for use as an agent for rendering the transparent tissue of the eye visible. The method for suppressing the formation of coarse particles when an aqueous suspension of fine polylactic acid particles is freeze-dried includes: (a) a step in which an aqueous suspension of fine polylactic acid particles containing a dispersing agent and from 3.5% to 10% mannitol is prepared by (i) adding, while stirring, a solution of polylactic acid dissolved in a water miscible organic solvent to a dispersing agent aqueous solution and then adding mannitol, or (ii) adding, while stirring, the solution of polylactic acid dissolved in said solvent to a dispersing agent/mannitol aqueous solution containing a dispersing agent and mannitol; and (b) a step in which said suspension is freeze-dried in a glass container. The method for producing polylactic acid particles for use as an agent for rendering transparent tissue visible includes the steps (a) and (b).</p> |
