Claims
- 1. A method for forming microparticles comprising the steps of:
a) directing microdroplets of a mixture comprising a biocompatible polymer, a solvent for the polymer and a protein, peptide or small molecule, into a freezing section containing a liquefied gas, whereby the microdroplets freeze; and b) 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 the biocompatible polymer is biodegradable.
- 3. The method of claim 2, 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.
- 4. The method of claim 3, wherein the polymer is a poly(lactide-co-glycolide).
- 5. The method of claim 1, wherein the temperature of step (b) is lower than the temperature of step (c).
- 6. The method of claim 1, wherein the liquefied gas is sprayed into the freezing section.
- 7. The method of claim 1, wherein the frozen microdroplets are collected at the bottom of the freezing section and directed into the extraction section.
- 8. A method for forming microparticles comprising the steps of:
a) directing the microdroplets of a mixture comprising a biocompatible polymer, a solvent for the polymer and a protein, peptide or small molecule, into a freezing vessel containing a liquefied gas, whereby the microdroplets freeze; and b) 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.
- 9. The method of claim 8, wherein the biocompatible polymer is biodegradable.
- 10. The method of claim 9, 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.
- 11. The method of claim 8, wherein the polymer is a poly(lactide-co-glycolide).
- 12. The method of claim 8, wherein the temperature of step (b) is lower than the temperature of step (c).
- 13. The method of claim 8, wherein the liquefied gas is sprayed into the freezing vessel.
- 14. The method of claim 8, wherein the frozen microdroplets are collected at the bottom of the freezing vessel and directed into the extraction vessel.
RELATED APPLICATIONS
[0001] This application is a Continuation of pending U.S. patent application Ser. No. 10/006,991, filed on Dec. 6, 2001, which is a Continuation of pending U.S. patent application Ser. No. 09/587,821, filed on Jun. 6, 2000, 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.
Continuations (4)
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Number |
Date |
Country |
Parent |
10006991 |
Dec 2001 |
US |
Child |
10784474 |
Feb 2004 |
US |
Parent |
09587821 |
Jun 2000 |
US |
Child |
10006991 |
Dec 2001 |
US |
Parent |
09305413 |
May 1999 |
US |
Child |
09587821 |
Jun 2000 |
US |
Parent |
08443726 |
May 1995 |
US |
Child |
09305413 |
May 1999 |
US |