US5091206A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing magnetically responsive polymer particles and application thereof
Assignee: Baxter Healthcare Corp
•
Filing: 1989-05-30
•
Granted: 1992-02-25
•
Expires: 2009-05-30
Abstract
Abstract This invention provides a novel process of producing magnetically responsive polymer particles comprising polymeric core particles coated evenly with a layer of polymer containing magnetically responsive metal oxide. A wide variety of polymeric particles with sizes ranging from 1 to 100 microns can be used a core particles and transformed into magnetically responsive polymer particles. The surface of these magnetically responsive polymer particles can be coated further with another layer of functionalized polymer. These magnetically responsive polymer particles can be used for passive or covalent coupling of biological material such as antigens, antibodies, enzymes of DNA/RNA hybridization and used as solid phase for various types of immunoassays, DNA/RNA hybridization probes assays, affinity purification, cell separation and other medical, diagnostic, and industrial applications.
Inventors
- 👤 Chao-Huei Wang
- 👤 Dinesh O. Shah
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:40
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/28; B01J20/28002; B01J20/28004; A; A61; A61M; A61M1/00; A61M1/36; A61M1/3618; B01J20/28009; B01J20/28014; B01J20/28016; B01J8/00; B01J8/008; B03; B03C; B03C1/00; B03C1/005; B03C1/01; C; C08; C08F; C08F257/00; C08F257/02; C08F285/00; C12; C12Q; C12Q1/00; C12Q1/68; C12Q1/6813; C12Q1/6816; C12Q1/6834; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; G01N33/54326; G01N33/5434; G01N33/58; G01N33/582; G01N33/585; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/10; H01F1/11; H01F1/111; G01N2446/00; G01N2446/10; G01N2446/40; G01N2446/80; G01N2446/84; G01N2446/86
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
147 words
The process to make a magnetically responsive polymer particle having a polymeric core particle evenly covered by a metal oxide/polymer coating comprising producing a magnetic oxide particle with an average size of about I micron or less by heating an aqueous solution containing a mixture of divalent and trivalent transition metal salts in a molar ratio of divalent to trivalent metal salt of 0.5 to 2.0 under alkaline conditions to precipitate a metal oxide, washing said precipitate, breaking down the aggregate of said metal oxide crystals contained in said precipitate, and collecting the smaller sized metal oxide crystals of average size less than 1.0 micron, mixing said magnetic metal oxide particles with a monomer in a weight ratio of 0.1 to 12 to produce an admixture coating a polymeric core with said admixture in the presence of a polymerization initiator capable of initiating polymerization of said monomer.
Claim 2
Dependent Claim
147 words
The process to make a magnetically responsive polymer particle having a polymeric core particle evenly covered by a metal oxide/polymer coating comprising producing a magnetic oxide particle with an average size of about I micron or less by heating an aqueous solution containing a mixture of divalent and trivalent transition metal salts in a molar ratio of divalent to trivalent metal salt of 0.5 to 2.0 under alkaline conditions to precipitate a metal oxide, washing said precipitate, breaking down the aggregate of said metal oxide crystals contained in said precipitate, and collecting the smaller sized metal oxide crystals of average size less than 1.0 micron, mixing said magnetic metal oxide particles with a monomer in a weight ratio of 0.1 to 12 to produce an admixture coating a polymeric core with said admixture in the presence of a polymerization initiator capable of initiating polymerization of said monomer.
Claim 3
Dependent Claim
27 words
The process of claim 1 together with the further step of coating further with a functionalized monomer to provide functional groups for covalent binding of biological materials.
Claim 4
Dependent Claim
158 words
The process to make a magnetically responsive polymer particle covered by a metal oxide/crosslinked polymer coating inert to common solvents comprising producing a magnetic oxide particle with an average size of about 1 micron or less by heating an aqueous solution containing admixture of divalent and trivalent transition metal salts in a molar ratio of divalent to trivalent metal salt of 0.5 to 2.0 under alkaline conditions to precipitate a metal oxide, washing said precipitate, breaking down the aggregate of said metal oxide crystals contained in said precipitate, and collecting the smaller sized metal oxide crystals of average size less than 1.0 micron, mixing said suspended metal oxide particle with a monomer in a weight ratio of 0.1 to 12, said monomer containing 8 to 10 percent of a cross-linking agent, to produce an admixture, and coating a polymeric core particle with said admixture in the presence of a polymerization initiator capable of initiating polymerization of said monomer.
Claim 5
Dependent Claim
158 words
The process to make a magnetically responsive polymer particle covered by a metal oxide/crosslinked polymer coating inert to common solvents comprising producing a magnetic oxide particle with an average size of about 1 micron or less by heating an aqueous solution containing admixture of divalent and trivalent transition metal salts in a molar ratio of divalent to trivalent metal salt of 0.5 to 2.0 under alkaline conditions to precipitate a metal oxide, washing said precipitate, breaking down the aggregate of said metal oxide crystals contained in said precipitate, and collecting the smaller sized metal oxide crystals of average size less than 1.0 micron, mixing said suspended metal oxide particle with a monomer in a weight ratio of 0.1 to 12, said monomer containing 8 to 10 percent of a cross-linking agent, to produce an admixture, and coating a polymeric core particle with said admixture in the presence of a polymerization initiator capable of initiating polymerization of said monomer.
Claim 6
Dependent Claim
26 words
The process of claims 1, 2 or 3 wherein said monomer is selected from the group consisting of styrene, methyl methacrylate, vinyltoluene, divinylbenzene, and glycidyl methacrylate.
Claim 7
Dependent Claim
20 words
The process of claim 2 wherein said function group is selected from the group consisting of carboxyl, amino, and hydroxyl.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-02-24 | 1995-08-26 | 1996-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-24 | 1999-08-26 | 2000-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-24 | 2003-08-26 | 2004-02-25 | $7700.00 | Window Closed / Lapsed |