# US 2012/0083444 A1 · Emulsion Method For Preparing Low Residual Solvent Microparticles > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2012/0083444 A1 - Document ID: US20120083444A1 - Status: Published application - Kind: A1 - Application number: 13/247,577 - Filed: 2011-09-28 - Published: 2012-04-05 - Earliest claimed: 2010-09-30 - Inventors: Brenda Perkins; Asima Pattanaik - Web page: https://patentgrep.com/patent/US20120083444A1 ## CPC - A61K 9/1647: {Polyesters, e.g. poly(lactide-co-glycolide)} - A61K 9/1694: {resulting in granules or microspheres of the matrix type containing more than 5% of excipient} - A61K 31/00: Medicinal preparations containing organic active ingredients - A61K 38/31: Somatostatins - A61P 9/12: Antihypertensives - A61P 25/16: Anti-Parkinson drugs - A61P 25/20: Hypnotics; Sedatives - A61P 29/00: Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID] - A61P 31/00: Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics - A61P 37/02: Immunomodulators - A61P 37/08: Antiallergic agents (antiasthmatic agents A61P11/06; ophthalmic antiallergics A61P27/14) - A61P 43/00: Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00 - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS ## Abstract The method disclosed herein comprises using a non-polar alkane in the continuous phase of an emulsion process to aid in the removal of dispersed phase solvent from the microparticles. The microparticles can further be subjected to a post-production treatment process, involving a non-polar alkane suspension and a rinse, to further reduce residual dispersed phase solvent levels. ## Claims ### Claim 1 An emulsion, comprising: a dispersed phase, comprising: a biocompatible polymer dispersed or dissolved in a dispersed phase solvent comprising a C1-C4 halogenated alkane, ethyl acetate, or a combination thereof; and a continuous phase, comprising: a surfactant mixture and a non-polar alkane; wherein the surfactant mixture comprises at least 2% by weight of the non-polar alkane dissolved or dispersed therein; wherein the dispersed phase is dispersed in the continuous phase. ### Claim 2 (depends on 1) The emulsion of claim 1, wherein the surfactant mixture comprises sorbitan monostearate, sorbitan monooleate, polyoxyethylene sorbitan monooleate, or a combination thereof. ### Claim 3 (depends on 1) The emulsion of claim 1, wherein the biocompatible polymer comprises poly(lactide), poly(glycolide), poly(lactide-co-glycolide), poly(caprolactone), poly(lactide-co-caprolactone), polyethylene glycol, or a copolymer, blend, or mixture thereof. ### Claim 4 (depends on 1) The emulsion of claim 1, wherein the dispersed phase further comprises a bioactive agent. ### Claim 5 (depends on 4) The emulsion of claim 4, wherein the bioactive agent is water-soluble. ### Claim 6 (depends on 4) The emulsion of claim 4, wherein the bioactive agent is an oligopeptide. ### Claim 7 (depends on 4) The emulsion of any of claims 4, wherein the bioactive agent is octreotide. ### Claim 8 (depends on 1) The emulsion of claim 1, wherein the dispersed phase comprises at least 10% by weight of the biocompatible polymer. ### Claim 9 (depends on 1) The emulsion of claim 1, wherein the dispersed phase solvent comprises methylene chloride, chloroform, carbon tetrachloride, ethylene dichloride, ethylene chloride, 2,2,2-trichloroethane, or a mixture thereof. ### Claim 10 (depends on 1) The emulsion of claim 1, wherein the dispersed phase solvent comprises ethyl acetate. ### Claim 11 (depends on 1) The emulsion of claim 1, wherein the non-polar alkane comprises pentane, cyclopentane, hexanes, cyclohexane, heptane, or a combination thereof. ### Claim 12 (depends on 1) The emulsion of claim 1, wherein the non-polar alkane comprises heptane. ### Claim 13 A method for preparing microparticles, comprising: (a) providing a first phase comprising a biocompatible polymer dispersed or dissolved in a dispersed phase solvent comprising a C1-C4 halogenated alkane, ethyl acetate, or a combination thereof; (b) providing a second phase comprising a continuous phase surfactant mixture and a non-polar alkane; wherein the surfactant mixture comprises at least 2% by weight of the non-polar alkane dissolved or dispersed therein; (c) mixing the first and second phases to form an emulsion; and (d) removing at least a portion of the dispersed phase solvent to form microparticles. ### Claim 14 (depends on 13) The method of claim 13 wherein the first phase further comprises a bioactive agent. ### Claim 15 (depends on 13) The method of claim 13 wherein the first phase further comprises, dispersed therein, an inner aqueous phase comprising a bioactive agent dissolved or dispersed therein. ### Claim 16 (depends on 13) The method of claim 13, wherein the first phase further comprises, dispersed therein, a solid bioactive agent. ### Claim 17 (depends on 13) The method of claim 13, wherein the bioactive agent is an oligopeptide. ### Claim 18 (depends on 13) The method of claim 13, wherein the bioactive agent is octreotide. ### Claim 19 (depends on 13) The method of claim 13, wherein the first phase comprises at least 10% by weight of the biocompatible polymer. ### Claim 20 (depends on 13) The method of claim 13, wherein the surfactant mixture comprises sorbitan monostearate, sorbitan monooleate, polyoxyethylene sorbitan monooleate, or a combination thereof. ### Claim 21 (depends on 13) The method of claim 13, wherein the biocompatible polymer comprises poly(lactide), poly(glycolide), poly(lactide-co-glycolide), or a copolymer, blend, or mixture thereof. ### Claim 22 (depends on 13) The method of claim 13, wherein the dispersed phase solvent comprises methylene chloride, chloroform, carbon tetrachloride, ethylene dichloride, ethylene chloride, 2,2,2-trichloroethane, or a mixture thereof. ### Claim 23 (depends on 13) The method of claim 13, wherein the dispersed phase solvent comprises ethyl acetate. ### Claim 24 (depends on 13) The method of claim 13, wherein the non-polar alkane comprises pentane, cyclopentane, hexanes, cyclohexane, heptane, or a combination thereof. ### Claim 25 (depends on 13) The method of claim 13, wherein the non-polar alkane comprises heptane.