Star polymer nanoshells and methods of preparation thereof

Patent metadata

Field	Value
Publication number	US-9597405-B2
Application number	US-201514588584-A
Country	US
Kind code	B2
Filing date	Jan 2, 2015
Priority date	Mar 18, 2011
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A nanoshell is disclosed, comprising a star polymer occlusion complex comprising i) an amphiphilic unimolecular star polymer having a crosslinked core covalently linked to 6 or more independent polymer arms, and ii) a cargo material occluded in the star polymer; and a shell comprising an inorganic material in contact with a peripheral surface of the star polymer occlusion complex.

First claim

What is claimed is:

1. A nanoshell, comprising:
a star polymer occlusion complex comprising i) an amphiphilic unimolecular star polymer having a crosslinked polymer core covalently linked to 6 or more independent polymer arms, and ii) a cargo material occluded in the star polymer; and
a shell comprising iron oxide, the shell exterior to and in contact with a peripheral surface of the star polymer occlusion complex;
wherein the crosslinked polymer core is a product of a vinyl polymerization and/or a ring opening polymerization.

2. The nanoshell of claim 1 , wherein i) the core is hydrophobic, ii) the cargo material is hydrophobic, and iii) each of the 6 or more polymer arms comprises a) a hydrophobic chain segment covalently linked to the core and b) a peripheral hydrophilic chain segment linked to the hydrophobic chain segment.

3. The nanoshell of claim 1 , wherein an aqueous mixture of the nanoshell is suitable for diagnostic imaging.

4. The nanoshell of claim 1 , wherein the shell comprises one or more shell layers.

5. The nanoshell of claim 4 , wherein the one or more shell layers are porous.

6. The nanoshell of claim 1 , wherein the nanoshell has an average diameter of about 15 nm to about 300 nm.

7. The nanoshell of claim 1 , wherein the cargo material is an imaging agent.

8. The nanoshell of claim 1 , wherein the cargo material is a biologically active compound.

9. The nanoshell of claim 1 , wherein the star polymer comprises a polycarbonate chain segment, a polyester chain segment, or a combination thereof.

10. The nanoshell of claim 1 , further comprising an organic surface group covalently linked to the shell, the organic surface group comprising a chemical moiety selected from the group consisting of dyes, poly(alkylene oxide) chain segments, poly(alkylene imine) chain segments, biologically active moieties, and combinations thereof.

11. A method of forming the nanoshell of claim 1 , comprising:
forming a mixture containing a star polymer occlusion complex and iron oxide in a suitable solvent, the star polymer occlusion complex comprising i) an amphiphilic unimolecular star polymer having a crosslinked polymer core covalently linked to 6 or more independent polymer arms, and ii) a cargo material occluded in the star polymer; and
injecting the mixture into a second solvent, the second solvent being a non-solvent for the cargo material, thereby forming the nanoshell.

12. The method of claim 11 , wherein i) the core is hydrophobic, ii) the cargo material is hydrophobic, and iii) each of the 6 or more polymer arms comprises a) a hydrophobic chain segment covalently linked to the core and b) a peripheral hydrophilic chain segment linked to the hydrophobic chain segment.

13. The method of claim 11 , wherein the nanoshell has an average diameter of about 15 nm to about 300 nm.

14. The method of claim 11 , wherein the cargo material is an imaging agent.

15. The method of claim 11 , wherein the cargo material is a biologically active compound.

16. A tagged silica nanoshell, comprising:
a star polymer occlusion complex comprising i) an amphiphilic unimolecular star polymer having a crosslinked polymer core covalently linked to 6 or more independent polymer arms and ii) a cargo material occluded in the star polymer, wherein the crosslinked polymer core is a product of a vinyl polymerization and/or a ring opening polymerization;
a shell comprising silica, the shell exterior to and in contact with a peripheral surface of the star polymer occlusion complex; and
an organic surface group comprising a poly(alkylene oxide) chain segment covalently linked to the shell.

17. The tagged silica nanoshell of claim 16 , wherein i) the core is hydrophobic, ii) the cargo material is hydrophobic, and iii) each of the 6 or more polymer arms comprises a) a hydrophobic chain segment covalently linked to the core and b) a peripheral hydrophilic chain segment linked to the hydrophobic chain segment.

18. The tagged silica nanoshell of claim 16 , wherein an aqueous mixture of the tagged silica nanoshell is suitable for diagnostic imaging.

19. The tagged silica nanoshell of claim 16 , comprising a second organic surface group covalently linked to the shell, the second organic surface group comprising a chemical moiety selected from the group consisting of dyes, poly(alkylene imine) chain segments, biologically active moieties, and combinations thereof.

20. The tagged silica nanoshell of claim 16 , wherein the tagged silica nanoshell has an average diameter of about 15 nm to about 300 nm.

21. A method of forming the tagged silica nanoshell of claim 16 , comprising:
treating a star polymer occlusion complex with a first tetravalent silicon material, thereby forming a precursor silica nanoshell, wherein i) the star polymer occlusion complex comprises an amphiphilic unimolecular star polymer and a cargo material occluded therein, the star polymer having a crosslinked polymer core covalently linked to 6 or more independent polymer arms and ii) the crosslinked polymer core is a product of a vinyl polymerization and/or a ring opening polymerization;
treating the precursor nanoshell with a second tetravalent silicon material comprising a nucleophilic group, thereby forming a silica nanoshell comprising a shell which is exterior to and in contact with a peripheral surface of the star polymer occlusion complex, wherein the shell comprises i) silica and ii) nucleophilic surface groups selected from the group consisting of amines, thiols, alcohols, and combinations thereof; and
covalently linking to a nucleophilic surface group of the shell an organic surface group comprising a poly(alkylene oxide) chain segment, thereby forming the tagged silica nanoshell.

22. The method of claim 21 , wherein i) the core is hydrophobic, ii) the cargo material is hydrophobic, and iii) each of the 6 or more polymer arms comprises a) a hydrophobic chain segment covalently linked to the core and b) a peripheral hydrophilic chain segment linked to the hydrophobic chain segment.

23. The method of claim 21 , further comprising covalently linking to the shell a second organic surface group comprising a chemical moiety selected from the group consisting of dyes, poly(alkylene imine) chain segments, biologically active moieties, and combinations thereof.

Assignees

• IBM
• San Jose State Univ Res Found

Inventors

• Lee Victor Yee-Way
• Miller Robert D
• Nuno Hector H
• Sly Joseph

Classifications

• B82Y5/00

  Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery · CPC title

• C09B67/0032

  Treatment of phthalocyanine pigments (C09B67/0016, C09B67/0019 take precedence) · CPC title

• Y10T428/2993

  Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.] · CPC title

• Y10T428/249953

  Composite having voids in a component [e.g., porous, cellular, etc.] · CPC title

• A61K47/6929

  the form being a nanoparticle, e.g. an immuno-nanoparticle · CPC title