Emulsion/aggregation polymeric microspheres for biomedical applications and methods of making same
View Patent ↗A method of forming polymeric microspheres for biomedical applications includes forming polymeric microspheres by an emulsion/aggregation process from a precursor monomer species, and treating the polymeric microspheres to attach a biomedical functional material to the polymeric microspheres, where the polymeric microspheres have an average particle diameter of from about 1 to about 15 microns with a narrow particle geometric size distribution. The biomedical functional material may be, for example, a radioactive material, a radioactive precursor material, a bioactive agent, or a ligand.
1. A method of forming polymeric microspheres for biomedical applications, comprising:
forming polymeric microspheres by an emulsion/aggregation process from a precursor monomer species; and
attaching a biomedical functional material selected from the group consisting of a radioactive material, radioactive precursor material, a bioactive agent, and a ligand to said polymeric microspheres,
wherein said polymeric microspheres have an average particle diameter of from about 1 to about 15 microns with a narrow particle geometric size distribution of less than about 1.25, and
wherein said emulsion/aggregation process comprises forming a polymeric resin from said precursor monomer species and aggregating and coalescing said polymeric resin into polymeric microspheres.
2. The method of claim 1 , wherein said biomedical functional material is a ligand.
3. The method of claim 2 , wherein said ligand is a pharmacologically active compound selected from the group consisting of peptides, enzymes, analytes, antigens, and antibodies.
4. The method of claim 2 , wherein said ligand is an antigen selected from the group consisting of protein, peptide, polysaccharide, glycoprotein, glycolipid, nucleic acid, and mixtures thereof.
5. The method of claim 1 , wherein said biomedical functional material is a radioactive material or a radioactive precursor material.
6. The method of claim 5 , wherein said biomedical functional material is selected from the group consisting of yttrium-89, yttrium-90, phosphorus-31, and phosphorus-32.
7. The method of claim 1 , wherein said biomedical functional material is a bioactive agent.
8. The method of claim 7 , wherein said bioactive agent is a medicament.
9. The method of claim 7 , wherein said bioactive agent is selected from the group consisting of antibiotics, antimicrobials, antiseptics, bacteriocins, bacteriostats, disinfectants, steroids, anesthetics, fungicides, anti-inflammatory agents, antibacterial agents, antiviral agents, antitumor agents, growth promoters, and mixtures thereof.
10. The method of claim 1 , wherein the biomedical functional material is attached to said polymeric microspheres by at least one of covalent bonding, complexation, physical adsorption and physical absorption.
11. The method of claim 1 , wherein the polymeric microspheres are formed from said precursor monomer species and one or more additives.
12. The method of claim 11 , wherein the one or more additives are selected from the group consisting of colorants, fluorescent materials, magnetic materials, superparamagnetic materials, and bioactive agents.
13. The method of claim 12 , wherein the one or more additives comprises a colorant.
14. The method of claim 12 , wherein the one or more additives comprises a magnetic material.
15. The method of claim 14 , wherein the magnetic material is a magnetite.
16. The method of claim 12 , wherein the one or more additives comprises a superparamagnetic material.
17. The method of claim 12 , wherein the one or more additives comprises a bioactive agent.
18. The method of claim 17 , wherein the bioactive agent is encapsulated in said polymeric microsphere.
19. The method of claim 1 , further comprising surface treating said polymeric microspheres subsequent to said forming step but prior to said treating step, to alter a chemical property of a surface of said polymeric microspheres.
20. The method of claim 19 , wherein said chemical property is selected from the group consisting of hydrophobicity, hydrophilicity, surface charge, and presence of functional groups.
21. The method of claim 1 , wherein the polymeric microspheres are biocompatible.
22. The method of claim 1 , wherein the polymeric microspheres are biodegradable.
23. The method of claim 1 , wherein the polymeric microspheres are non-biodegradable.
24. The method of claim 1 , wherein said emulsion/aggregation process comprises:
forming a polymeric resin from said precursor monomer species;
aggregating said polymeric resin into polymeric particles;
coalescing said polymeric particles into polymeric microspheres; and
optionally isolating said polymeric microspheres.
25. The method of claim 1 , wherein said emulsion/aggregation process comprises:
forming a polymeric resin from said precursor monomer species;
forming an emulsion comprising said polymeric resin;
coalescing said polymeric resin into polymeric microspheres; and
optionally isolating said polymeric microspheres.
26. The method of claim 1 , wherein said emulsion/aggregation process comprises:
providing a polyester resin formed from said monomeric species;
dispersing said polyester resin in an aqueous media optionally comprising a surfactant, to provide a suspension of suspended particles of said polyester resin;
homogenizing said suspension;
aggregating and coalescing said homogenized suspension by adding a cationic metal salt and optional additives, and heating the aggregates, to form polymeric microspheres; and
optionally isolating said polymeric microspheres.
27. The method of claim 26 , wherein said hearing is conducted at or near a glass transition temperature of the polyester resin.
28. The method of claim 1 , wherein a polymer formed from said precursor monomer species is a functionalized polymer.