A method of separating biologically ingestible microparticles is used to obtain biologically ingestible microparticles in a thin film fluid formed between two
processing surfaces provided with a solution containing a first
solvent in which an objective substance to be pulverized is dissolved and a
solvent capable of serving as a second
solvent in which the
solubility of the microparticles is lower than in the first solvent, the two
processing surfaces being arranged so as to be able to approach to and separate from each other, at least one of which rotates relative to the other.In the method for producing biologically ingestible microparticles by separating raw materials of biologically ingestible microparticles by a
neutralization reaction in a fluid, the fluid is formed into a thin film fluid between two
processing surfaces arranged so as to be able to approach to and separate from each other, at least one of which rotates relative to the other, and biologically ingestible microparticles are separated by a
neutralization reaction in the thin film fluid.A solution containing a first solvent in which a chemical as a main
eye drop component is dissolved, and a solvent capable of serving as a second solvent in which the
solubility of the chemical is lower than in the first solvent, are mixed in a thin film fluid formed between two processing surfaces arranged so as to be able to approach to and separate from each other, at least one of which rotates relative to the other, thereby separating
drug particles and providing suspended eye drops based on the
drug particles.