Claims
- 1. A method for forming microparticles comprising the steps of:a) atomizing a mixture comprising a biocompatible polymer, a solvent for the polymer and a biologically active agent, to form microdroplets; b) directing the microdroplets into a freezing section containing a liquefied gas, whereby the microdroplets freeze; and c) contacting the frozen microdroplets in an extraction section with a liquid non-solvent to extract the solvent into the non-solvent thereby forming said microparticles; wherein the freezing section and extraction section are separated, and the non-solvent is in the liquid state throughout the method.
- 2. The method of claim 1 wherein said biologically active agent is selected from the group consisting of immunoglobulin proteins, interleukins, interferons, erythropoietin, antibodies, cytokines, hormones, antigens, growth factors, nucleases, tumor enzymes, tumor suppression genes, antisense molecules, antibiotics, anesthetics, sedatives, cardiovascular agents, antitumor agents, antineoplastics, antihistamines and vitamins.
- 3. The method of claim 2 wherein the biologically active agent is a protein.
- 4. The method of claim 1 wherein the biocompatible polymer is biodegradable.
- 5. The method of claim 4 wherein said biocompatible and biodegradable polymer is selected from the group consisting of poly(lactide)s, poly(glycolide)s, poly(lactide-co-glycolide)s, poly(lactic acid)s, poly(glycolic acid)s, polycarbonates, polyesteramides, polyanhydrides, poly(amino acids), polyorthoesters, polycaprolactone, poly(dioxanone)s, poly(alkylene alkylate)s, polyurethanes, blends and copolymers thereof.
- 6. The method of claim 5 wherein the polymer is a poly(lactide-co-glycolide).
- 7. The method of claim 1 wherein the temperature of step (b) is lower than the temperature of step (c).
- 8. The method of claim 1 wherein the liquefied gas is sprayed into the freezing section.
- 9. The method of claim 1 wherein the frozen microdroplets are collected at the bottom of the freezing section and directed into the extraction section.
- 10. A method for forming microparticles comprising the steps of:a) atomizing a mixture comprising a biocompatible polymer, a solvent for the polymer and a biologically active agent, to form microdroplets; b) directing the microdroplets into a freezing vessel containing a liquefied gas, whereby the microdroplets freeze; and c) contacting the frozen microdroplets in an extraction vessel with a liquid non-solvent to extract the solvent into the non-solvent thereby forming said microparticles; wherein the freezing vessel and extraction vessel are separated, and the non-solvent is in the liquid state throughout the method.
- 11. The method of claim 10 wherein said biologically active agent is selected from the group consisting of immunoglobulin proteins, interleukins, interferons, erythropoietin, antibodies, cytokines, hormones, antigens, growth factors, nucleases, tumor enzymes, tumor suppression genes, antisense molecules, antibiotics, anesthetics, sedatives, cardiovascular agents, antitumor agents, antineoplastics, antihistamines and vitamins.
- 12. The method of claim 11 wherein the biologically active agent is a protein.
- 13. The method of claim 10 wherein the biocompatible polymer is biodegradable.
- 14. The method of claim 13 wherein said biocompatible and biodegradable polymer is selected from the group consisting of poly(lactide)s, poly(glycolide)s, poly(lactide-co-glycolide)s, poly(lactic acid)s, poly(glycolic acid)s, polycarbonates, polyesteramides, polyanhydrides, poly(amino acids), polyorthoesters, polyacetals, polycyanoacrylates, polyetheresters, polycaprolactone, poly(dioxanone)s, poly(alkylene alkylate)s, polyurethanes, blends and copolymers thereof.
- 15. The method of claim 14 wherein the polymer is a poly(lactide-co-glycolide).
- 16. The method of claim 10 wherein the temperature of step (b) is lower than the temperature of step (c).
- 17. The method of claim 10 wherein the liquefied gas is sprayed into the freezing vessel.
- 18. The method of claim 10 wherein the frozen microdroplets are collected at the bottom of the freezing vessel and directed into the extraction vessel.
- 19. The method of claim 1, wherein the biologically active agent is dissolved in the mixture.
- 20. The method of claim 1, wherein the biologically active agent is suspended in the mixture.
- 21. The method of claim 1, wherein the biologically active agent forms an emulsion in the mixture.
- 22. The method of claim 10, wherein the biologically active agent is dissolved in the mixture.
- 23. The method of claim 10, wherein the biologically active agent is suspended in the mixture.
- 24. The method of claim 10, wherein the biologically active agent forms an emulsion in the mixture.
RELATED APPLICATIONS
This application is a Continuation of U.S. patent application Ser. No. 09/587,821, filed on Jun. 6, 2000, now U.S. Pat. No. 6,358,443, which is a Continuation of U.S. patent application Ser. No. 09/305,413, filed on May 5, 1999, now U.S. Pat. No. 6,153,129, which is a Continuation of U.S. patent application Ser. No. 08/443,726, filed on May 18, 1995, now U.S. Pat. No. 5,922,253, the entire teachings of which are incorporated herein by reference.
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Foreign Referenced Citations (4)
Number |
Date |
Country |
WO 8903678 |
May 1989 |
WO |
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Nov 1990 |
WO |
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Continuations (3)
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09/587821 |
Jun 2000 |
US |
Child |
10/006991 |
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Parent |
09/305413 |
May 1999 |
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09/587821 |
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08/443726 |
May 1995 |
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09/305413 |
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US |