Patent EP0240770A1 successfully refreshed from Google Patents.
EP0240770A1
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Coated chromium dioxide particles
Assignee: EIDP Inc
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Filing: 1987-03-14
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Granted: —
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Expires: 2007-03-14
Abstract
Abstract Chromium dioxide has favourable magnetic properties which make it desirable as a solid support in heterogeneous immunoassays. However, to be useful in such assays it must be protected against hydrolytic degradation. This invention provides magnetic particles useful in immunoassays having a core of Cr0 2 which has a reduced surface, the core coated with silica and further coated with a silane.
Inventors
- 👤 Hon-Peng Phillip Lau
- 👤 Esther Koo Yang
- 👤 Howard Wayne Jacobson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 23:08
CPC Classifications
B; B03; B03C; B03C1/00; B03C1/005; B03C1/01; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; G01N33/54326; G01N33/5434; G01N2446/00; G01N2446/20; G01N2446/80; G01N2446/86; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2993; Y10T428/2995
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
132 words
A magnetic particle useful as a solid support for bioaffinity separations or immunoassays comprising: a core of acicular rutile chromium dioxide having a specific surface area of 5-100 m 2 /g. said chromium dioxide particle having a reduced surface characterized by a line in the X-ray diffraction pattern of the reduced chromium dioxide corresponding to an interplanar spacing of 316.8 pm: said core having an inorganic surface layer coating which resists oxygen diffusion: said inorganic surface layer coated core having an outer layer of a silane compound capable of binding proteins, ligands, haptens or linker compounds directly or through intermediate coupling agents to said inorganic surface layer coated core: said magnetic particle having a mean volume diameter of from .5 to 10 µm, and a remanent magnetization of less than 25 emu.
Claim 2
Dependent Claim
132 words
A magnetic particle useful as a solid support for bioaffinity separations or immunoassays comprising: a core of acicular rutile chromium dioxide having a specific surface area of 5-100 m 2 /g. said chromium dioxide particle having a reduced surface characterized by a line in the X-ray diffraction pattern of the reduced chromium dioxide corresponding to an interplanar spacing of 316.8 pm: said core having an inorganic surface layer coating which resists oxygen diffusion: said inorganic surface layer coated core having an outer layer of a silane compound capable of binding proteins, ligands, haptens or linker compounds directly or through intermediate coupling agents to said inorganic surface layer coated core: said magnetic particle having a mean volume diameter of from .5 to 10 µm, and a remanent magnetization of less than 25 emu.
Claim 3
Dependent Claim
25 words
The particle of Claim 1 wherein the inorganic surface layer is silica. The weight ratio of silica to CrO 2 being greater than about 1%.
Claim 4
Dependent Claim
26 words
The particle of Claim 2 wherein the reduced core is coated with alumina, the weight ratio of alumina to CrO 2 being greater than about 0.1%.
Claim 5
Dependent Claim
21 words
A particle of Claim 2 or 3 wherein said silica coating contains 0.04 to 6% B 2 0 3 by weight.
Claim 6
Dependent Claim
24 words
5 . A particle of Claim 4 wherein the silane is selected from the group consisting of 3-aminopropyltriethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane. diphenyldiethoxysilane, 1-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane, and n-dodecyl- triethoxysilane.
Claim 7
Dependent Claim
10 words
A particle of Claim 5 wherein the silane is 3-aminopropyltriethoxysilane.
Claim 8
Dependent Claim
39 words
A particle of Claim 2 or 3 in which the weight ratio of SiO 2 to CrO 2 is 2 to 6% and the chromium dioxide core has a specific surface area of 30- 80 m 2 / g.
Claim 9
Dependent Claim
39 words
A particle of Claim 2 or 3 in which the weight ratio of Sio 2 to CrO 2 is 2 to 6% and the chromium dioxide core has a specific surface area of 40- 70 m 2 / g.
Claim 10
Dependent Claim
19 words
A particle of Claim 7 wherein said silica coating contains 0.04 to 6% B 2 0 3 by weight.
Claim 11
Dependent Claim
19 words
A particle of Claim 8 wherein said silica coating contains 0.04 to 6% B 2 0 3 by weight.
Claim 12
Dependent Claim
22 words
A particle of Claim 7 wherein the silane is selected from the group consisting of 3-aminopropyltriethoxysilane. N-2-aminoethyl-3-aminopropyltriethoxysilane, diphenyldiethoxysilane, 1-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane, and n-dodecyl- triethoxysilane.
Claim 13
Dependent Claim
22 words
A particle of Claim 8 wherein the silane is selected from the group consisting of 3-aminopropyltriethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane, diphenyldiethoxysilane, 1-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane, and n-dodecyl- triethoxysilane.
Claim 14
Dependent Claim
25 words
1 3 . A particle of Claim 9 wherein the silane is selected from the group consisting of 3-aminopropyltriethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane, diphenyldiethoxysilane, 1-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane, and n-dodecyl- triethoxysilane.
Claim 15
Dependent Claim
22 words
A particle of Claim 10 wherein the silane is selected from the group consisting of 3-aminopropyltriethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane, diphenyldiethoxysilane, 1-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane, and n-dodecyl- triethoxysilane.
Claim 16
Independent Claim
20 words
A method of heterogeneous immunoassay wherein the particle of Claims 1, 2 or 3 is used as a solid support.
Claim 17
Independent Claim
19 words
A method of bioaffinity separation wherein the particle of Claims 1, 2 or 3 is used as support material.
Claim 18
Dependent Claim
44 words
A method of Claim 15 wherein said silica contains 0.04-6% B 2 0 3 by weight, the weight ratio of SiO 2 to CrO 2 is 2-6% and the silane is selected from the group consisting of 3-amino-propyltri-ethoxysilane, N-2-aminoethyl-3-aminopropyl-triethoxysilane, diphenyldiethoxysilane, 1-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane, and n-dodecyl- triethoxysilane.
Claim 19
Independent Claim
43 words
A method of bioaffinity separation wherein said silica contains 0.04-6% B 2 O 3 by weight, the weight ratio of Sio 2 to CrO 2 is 2-6% and the silane is selected from the group consisting of 3-amino-propyltri-ethoxysilane, N-2-aminoethyl-3-aminopropyl-triethoxy-silane, diphenyldiethoxysilane. l-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane. and n-dodecyl-triethoxysilane.
Claim 20
Independent Claim
43 words
A method of bioaffinity separation wherein said silica contains 0.04-6% B 2 O 3 by weight, the weight ratio of Sio 2 to CrO 2 is 2-6% and the silane is selected from the group consisting of 3-amino-propyltri-ethoxysilane, N-2-aminoethyl-3-aminopropyl-triethoxy-silane, diphenyldiethoxysilane. l-trimethoxy-2-(m,p-chloromethyl)phenylethanesilane. and n-dodecyl-triethoxysilane.
References Cited (Backward Citations)
US4177253A
Cited
EP0125995A2
Cited
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