US4157323A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metal containing polymeric functional microspheres
Assignee: California Institute of Technology
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Filing: 1977-04-20
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Granted: 1979-06-05
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Expires: 1997-04-20
Abstract
Abstract Polymeric functional microspheres containing metal or metal compounds are formed by addition polymerization of a covalently bondable olefinic monomer such as hydroxyethylmethacrylate in the presence of finely divided metal or metal oxide particles, such as iron, gold, platinum or magnetite, which are embedded in the resulting microspheres. The microspheres can be covalently bonded to chemotherapeutic agents, antibodies, or other proteins providing a means for labeling or separating labeled cells. Labeled cells or microspheres can be concentrated at a specific body location such as in the vicinity of a malignant tumor by applying a magnetic field to the location and then introducing the magnetically attractable microspheres or cells into the circulatory system of the subject. Labeled cells can be separated from a cell mixture by applying a predetermined magnetic field to a tube in which the mixture is flowing. After collection of the labeled cells, the magnetic field is discontinued and the labeled sub-cell population recovered.
Inventors
- 👤 Shiao-Ping S. Yen
- 👤 Alan Rembaum
- 👤 Robert S. Molday
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:17
CPC Classifications
B; B01; B01J; B01J19/00; B01J19/24; B01J19/2415; B01J19/2435; A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5094; C; C08; C08F; C08F2/00; C08F2/44; C08K; C08K9/00; C08K9/08; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/58; G01N33/585; Y; Y10; Y10S; Y10S524/00; Y10S524/90
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
142 words
A composition comprising an aqueous suspension of small polymeric microspheres having a size of no more than 2000 A and containing a dispersion of 1 to 50% by weight of finely divided, metal containing particles having a size less than the resultant microspheres embedded within the microspheres and being selected from metals or metal compounds of electron dense metals having an atomic number above 50 or magnetically attractable metals and consisting essentially of the addition polymerizate of a monomer mixture consisting essentially of at least 20% by weight of a first ethylenically unsaturated acrylic monomer substituted with at least one covalent bonding functional group selected from amino, hydroxyl or carboxyl; 40% to 70% by weight of a sparingly water-soluble, compatible, unsaturated, second monomer having hydrophobic characteristics, and 1% to 20% by weight of a water-soluble, polyunsaturated, compatible diene or triene cross-linking agent.
Claim 2
Dependent Claim
142 words
A composition comprising an aqueous suspension of small polymeric microspheres having a size of no more than 2000 A and containing a dispersion of 1 to 50% by weight of finely divided, metal containing particles having a size less than the resultant microspheres embedded within the microspheres and being selected from metals or metal compounds of electron dense metals having an atomic number above 50 or magnetically attractable metals and consisting essentially of the addition polymerizate of a monomer mixture consisting essentially of at least 20% by weight of a first ethylenically unsaturated acrylic monomer substituted with at least one covalent bonding functional group selected from amino, hydroxyl or carboxyl; 40% to 70% by weight of a sparingly water-soluble, compatible, unsaturated, second monomer having hydrophobic characteristics, and 1% to 20% by weight of a water-soluble, polyunsaturated, compatible diene or triene cross-linking agent.
Claim 3
Dependent Claim
27 words
A composition according to claim 1 in which the first monomer is selected from acrylamide, methacrylamide, acrylic acid, methacrylic acid, hydroxy-lower alkyl acrylates or amino-lower alkyl acrylates.
Claim 4
Dependent Claim
25 words
A composition according to claim 2 in which the second monomer is selected from C 1 to C 8 lower alkyl acrylates or vinyl pyridines.
Claim 5
Dependent Claim
17 words
A composition according to claim 1 in which the size range in from 300 to 2000 Angstroms.
Claim 6
Dependent Claim
16 words
A composition according to claim 1 in which the metal has an atomic number above 75.
Claim 7
Dependent Claim
16 words
A composition according to claim 1 in which the particles are Fe 3 O 4 .
Claim 8
Independent Claim
154 words
A method of forming fine-sized metal containing polymeric, functional microspheres comprising the steps of: forming an aqueous solution of an ethylenically unsaturated monomer mixture consisting essentially of: at least 20% by weight of acrylic monomer substituted with a functional group selected from amino, hydroxyl or carboxyl; 40% to 70% by weight of a sparingly water-soluble, compatible, unsaturated, second monomer having hydrophobic characteristics, and 1% to 20% by weight of a water-soluble, polyunsaturated, compatible diene or triene cross-linking agent; dispersing in the solution 1 to 20% by weight of finely divided particles having a size less than the resultant microspheres and being selected from metals or metal compounds of electron dense metals having an atomic number above 50 or magnetically attractable metals; and addition polymerizing the monomer mixture to form a suspension of microspheres having a size of no more than 2000 Angstroms and containing 1 to 50% by weight of said metal embedded therein.
Claim 9
Independent Claim
154 words
A method of forming fine-sized metal containing polymeric, functional microspheres comprising the steps of: forming an aqueous solution of an ethylenically unsaturated monomer mixture consisting essentially of: at least 20% by weight of acrylic monomer substituted with a functional group selected from amino, hydroxyl or carboxyl; 40% to 70% by weight of a sparingly water-soluble, compatible, unsaturated, second monomer having hydrophobic characteristics, and 1% to 20% by weight of a water-soluble, polyunsaturated, compatible diene or triene cross-linking agent; dispersing in the solution 1 to 20% by weight of finely divided particles having a size less than the resultant microspheres and being selected from metals or metal compounds of electron dense metals having an atomic number above 50 or magnetically attractable metals; and addition polymerizing the monomer mixture to form a suspension of microspheres having a size of no more than 2000 Angstroms and containing 1 to 50% by weight of said metal embedded therein.
Claim 10
Dependent Claim
17 words
A method according to claim 7 in which the size range is from 300 to 2000 Angstroms.
Claim 11
Dependent Claim
16 words
A method according to claim 7 in which the metal has an atomic number above 75.
Claim 12
Dependent Claim
16 words
A method according to claim 2 in which the particles are Fe 3 O 4 .
Claim 13
Dependent Claim
21 words
A method according to claim 7 in which the addition polymerization is effected by irradiating the dispersion with high energy radiation.
Claim 14
Dependent Claim
21 words
A method according to claim 11 in which the radiation is 0.5 to 5.0 megarads from a cobalt 60 gamma source.
Claim 15
Dependent Claim
25 words
A method according to claim 11 in which the monomer mixture is present in the solution in an amount from 0.1 to 40% by weight.
Claim 16
Dependent Claim
28 words
A method according to claim 13 in which the first monomer is selected from acrylamide, methacrylamide, acrylic acid, methacrylic acid, hydroxy-lower alkyl acrylates or amino lower alkyl acrylates.
Claim 17
Dependent Claim
69 words
A method according to claim 14 in which the acrylates are selected from compounds of the formula: ##STR2## where R 1 is hydrogen or lower alkyl of 1-8 carbon atoms, R 2 is alkylene of 1-12 carbon atoms, Z is OH or R 3 --N 1 --R 4 where R 3 or R 4 are H, lower alkyl of 1-8 carbon atoms or lower alkoxy of 1-8 carbon atoms.
Claim 18
Dependent Claim
22 words
A method according to claim 15 in which the acrylate is selected from 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-dimethylaminoethyl methacrylate or 2-aminoethyl methacrylate.
Claim 19
Dependent Claim
25 words
A method according to claim 7 in which the second monomer is selected from C 1 to C 8 lower alkyl acrylates or vinyl pyridines.
Claim 20
Dependent Claim
19 words
A method according to claim 9 in which the metal is selected from Pb, Co, Pt, Au or Fe.
Claim 21
Dependent Claim
13 words
A method according to claim 7 in which the particles are magnetically attractable.
Claim 22
Dependent Claim
21 words
A method according to claim 19 in which the particles are selected from Fe, Ni, Co, alloys thereof or oxides thereof.
Claim 23
Dependent Claim
24 words
A method according to claim 11 further including the step of raising the pH of the microsphere suspension to about 7 to reduce agglomeration.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-06-04 | 1982-12-04 | 1983-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-06-04 | 1986-12-04 | 1987-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-06-04 | 1990-12-04 | 1991-06-05 | $7700.00 | Window Closed / Lapsed |