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US5204457A
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Organic magnetic complex
Assignee: Meito Sangyo KK
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Filing: 1990-10-19
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Granted: 1993-04-20
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Expires: 2010-10-19
Abstract
Abstract A complex of a carboxyalkyl ether of a polysaccharide with a magnetic metal oxide. This complex is extremely excellent in stability in preservation in the form of aqueous sol and has only a low toxicity, and thus is useful, for example, for medical use as a nuclear magnetic imaging molding agent or the like.
Inventors
- 👤 Shigeo Maruno
- 👤 Masakatsu Hasegawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:50
CPC Classifications
A; A61; A61K; A61K49/00; A61K49/06; A61K49/18; A61K49/1818; A61K49/1821; A61K49/1824; A61K49/1827; A61K49/1851; A61K49/1863; C; C08; C08B; C08B11/00; C08B11/20; C08B37/00; C08B37/0006; C08B37/0009; C08B37/0021; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
28 words
A complex of a carboxyalkyl ether of a polysaccharide having an intrinsic viscosity of about 0.02 to about 0.05 dl/g at 25° C. with a magnetic metal oxide.
Claim 2
Dependent Claim
28 words
A complex of a carboxyalkyl ether of a polysaccharide having an intrinsic viscosity of about 0.02 to about 0.05 dl/g at 25° C. with a magnetic metal oxide.
Claim 3
Dependent Claim
12 words
The complex of claim 1 wherein the polysaccharide is a neutral polysaccharide.
Claim 4
Dependent Claim
20 words
The complex of claim 2 wherein the polysaccharide is selected from the group consisting of dextran, starch, cellulose and pullulan.
Claim 5
Dependent Claim
25 words
The complex of claim 1 wherein the carboxyalkyl ether is at least one selected from a carboxymethyl ether, a carboxyethyl ether and a carboxypropyl ether.
Claim 6
Dependent Claim
30 words
The complex of claim 1 wherein the carboxyalkyl ether of the polysaccharide has an intrinsic viscosity in . the range of about 0.05 to about 0.3 dl/g at 25° C.
Claim 7
Dependent Claim
26 words
The complex of claim 1 wherein the carboxyalkyl ether of the polysaccharide has a substitution degree in the range of about 0.05 to about 1.0 mol/MSU.
Claim 8
Dependent Claim
44 words
The complex of claim 1 wherein the magnetic metal oxide is represented by the formula (M.sup.II O).sub.l.M.sub.2.sup.III O.sub.3 wherein M II denotes a divalent metal atom, M III denotes a trivalent metal atom and l is a real number in the range of 0≦l≦1.
Claim 9
Dependent Claim
36 words
The complex of claim 7 wherein the magnetic metal oxide is a ferrite represented by the formula (M.sup.II O)m.Fe.sub.2 O.sub.3 wherein M II denotes a divalent metal atom and m is a real number of 0≦m≦1.
Claim 10
Dependent Claim
32 words
The complex of claim 8 wherein the magnetic metal oxide is a magnetic iron oxide represented by the formula (FeO)n.Fe.sub.2 O.sub.3 wherein n is a real number in the range of 0≦n≦1.
Claim 11
Dependent Claim
15 words
The complex of claim 9 wherein the magnetic iron oxide is γ-iron oxide or magnetite.
Claim 12
Dependent Claim
37 words
The complex of claim 1 wherein the magnetic metal oxide is represented by the formula M.sup.II M.sup.IV O.sub.3 or M.sup.IV O.sub.2 wherein M II represents a divalent metal atom and M IV represents a tetravalent metal atom.
Claim 13
Dependent Claim
22 words
The complex of claim 11 wherein the magnetic metal oxide is selected from NiMnO 3 , CoMnO 3 and CrO 2 .
Claim 14
Dependent Claim
21 words
The complex of claim 1 wherein the magnetic metal oxide has a particle size of about 2 to about 100 nm.
Claim 15
Dependent Claim
39 words
The complex of claim 1 wherein the magnetic metal oxide has a magnetization in the range of about 1 to about 150 emu per 1 g of the metal in a magnetic field of 1 tesla at 20° C.
Claim 16
Dependent Claim
39 words
The complex of claim 1 wherein the magnetic metal oxide has a magnetization in the range of about 10 to about 150 emu per 1 g of the metal in a magnetic fieled of 1 tesla at 20° C.
Claim 17
Dependent Claim
36 words
The complex of claim 1 wherein the carboxyalkyl ether of the polysaccharide is contained in an amount of 0.05 to 10 parts by weight per part by weight of the metal in the magnetic metal oxide.
Claim 18
Dependent Claim
37 words
The complex of claim 1 wherein the carboxyalkyl ether of the polysaccharide is contained in an amount of 0.2 to 5 parts by weight per 1 part by weight of the metal in the magnetic metal oxide.
Claim 19
Dependent Claim
22 words
The complex of claim 1 wherein the diameter thereof measured by the light scattering method is about 10 to about 500 nm.
Claim 20
Dependent Claim
10 words
A MRI molding agent comprising the complex of claim 1.
Claim 21
Dependent Claim
115 words
A process for preparing the complex of claim 1 which comprises: (a) reacting an aqueous sol or suspension containing particles of a magnetic metal oxide with the carboxyalkyl ether of a polysaccharide having an intrinsic viscosity of about 0.02 to about 0.5 dl/g and a substitution degree of about 0.05 to about 1.0 mol/MSU, or (b) carrying out the reaction by mixing a salt of a divalent metal, a salt of a trivalent metal and a base while stirring in an aqueous system in the presence of the carboxyalkyl ether of the polysaccharide having an intrinsic viscosity of about 0.02 to about 0.5 dl/g and a substitution degree of about 0.05 to about 0.5 mol/MSU.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1996-04-19 | 1996-10-19 | 1997-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-04-19 | 2000-10-19 | 2001-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-04-19 | 2004-10-19 | 2005-04-20 | $7700.00 | Window Closed / Lapsed |