Patent ID: 7037528

Claim:
A method for preparing submicron sized particles of an organic compound, the solubility of which is greater in a water-miscible first solvent than in a second solvent which is aqueous, the process comprising the steps of (i) dissolving the organic compound in the water-miscible first solvent to form a solution, the first solvent being selected from the group consisting of N-methyl-2-pyrrolidinone, 2-pyrrolidone, dimethyl sulfoxide, dimethylacetamide, lactic acid, methanol, ethanol, isopropanol, 3-pentanol, n-propanol, glycerol, butylene glycol, ethylene glycol, propylene glycol, mono- and diacylated monoglycerides, dimethyl isosorbide, acetone, dimethylformamide, 1,4-dioxane, polyethylene glycol, polyethylene glycol esters, polyethylene glycol sorbitans, polyethylene glycol monoalkyl ethers, polypropylene glycol, polypropylene alginate, PPG-10 butanediol, PPG-10 methyl glucose ether, PPG-20 methyl glucose ether, PPG-15 stearyl ether, propylene glycol dicaprylate, propylene glycol dicaprate, propylene glycol laurate; (ii) mixing into the solution a first surface modifier selected from the group consisting of anionic surfactants, cationic surfactants and nonionic surfactants; (iii) mixing into the second solvent, a second surface modifier to define a second solution, the second surface modifier selected from the group consisting of: anionic surfactants, cationic surfactants and nonionic surfactants; and (iv) mixing the first solution with the second solution with high energy agitation by homogenization, counter-current flow homogenization, or microfluidization to define a pre-suspension of non-spherical, crystalline particles having an average effective particle size of less than 2 μm.