US4018886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diagnostic method and device employing protein-coated magnetic particles
Assignee: General Electric Co
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Filing: 1975-07-01
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Granted: 1977-04-19
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Expires: 1995-07-01
Abstract
Abstract Small magnetic particles are used to provide large and widely-distributed surface area for separating a select protein from a solution to enable detection thereof when present in low concentrations. The particles are coated with a protein that will interact specifically with the select protein.
Inventors
- 👤 Ivar Giaever
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:48
CPC Classifications
B; B03; B03C; B03C1/00; B03C1/02; B03C1/28; B03C1/288; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; G01N33/54326; B03C2201/00; B03C2201/18; B03C2201/26; G01N35/00; G01N2035/00465; G01N2035/00534; G01N35/0098; Y; Y10; Y10S; Y10S436/00; Y10S436/805; Y10S530/00; Y10S530/806; Y10S530/81; Y10S530/811
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
120 words
A diagnostic method for determining the presence or absence of select protein in a liquid sample comprising the steps of: dispersing a plurality of finely-divided magnetic particles each of which is coated with a layer directly bonded thereto of first protein molecules specific to said select protein in the sample liquid to facilitate contact between said coated particles and said sample liquid; magnetically retrieving and separating said coated particles from said sample liquid; washing said coated particles; introducing said coated particles into a volume of cleaving agent solution in direct contact with a metallized surface to permit select protein, if present, to detach from the first protein-coated particles and examining said metallized surface for the presence of protein adsorbed thereon.
Claim 2
Dependent Claim
120 words
A diagnostic method for determining the presence or absence of select protein in a liquid sample comprising the steps of: dispersing a plurality of finely-divided magnetic particles each of which is coated with a layer directly bonded thereto of first protein molecules specific to said select protein in the sample liquid to facilitate contact between said coated particles and said sample liquid; magnetically retrieving and separating said coated particles from said sample liquid; washing said coated particles; introducing said coated particles into a volume of cleaving agent solution in direct contact with a metallized surface to permit select protein, if present, to detach from the first protein-coated particles and examining said metallized surface for the presence of protein adsorbed thereon.
Claim 3
Dependent Claim
22 words
The diagnostic method recited in claim 1 wherein the magnetic particles are selected from the group consisting of ferromagnetic and ferrimagnetic materials.
Claim 4
Dependent Claim
19 words
The diagnostic method recited in claim 1 wherein the examining step is accomplished by the use of an ellipsometer.
Claim 5
Dependent Claim
25 words
The diagnostic method recited in claim 1 wherein the magnetic particles are held by means of an electrically induced magnetic field during the washing step.
Claim 6
Dependent Claim
17 words
The diagnostic method recited in claim 1 wherein the dispersing of the magnetic particles is accomplished magnetically.
Claim 7
Dependent Claim
14 words
The diagnostic method recited in claim 1 wherein the metallized surface is substantially planar.
Claim 8
Dependent Claim
13 words
The diagnostic method recited in claim 1 wherein the metallized surface is non-planar.
Claim 9
Dependent Claim
20 words
The diagnostic method recited in claim 1 wherein the specific protein is antigen and the select protein is antibody thereto.
Claim 10
Dependent Claim
20 words
The diagnositc method recited in claim 1 wherein the select protein is antigen and the specific protein is antibody thereto.
Claim 11
Dependent Claim
17 words
The diagnositc method recited in claim 1 wherein the cleaving agent solution is a weak acid solution.
Claim 12
Dependent Claim
20 words
The diagnostic method recited in claim 10 wherein the pH of the acid solution is in the range of 1-5.
Claim 13
Dependent Claim
13 words
The diagnostic method rectied in claim 10 wherein the acid is citric acid.
Claim 14
Dependent Claim
45 words
A diagnostic device for determining the presence or absence of select protein in a liquid sample comprising in combination a plurality of finely divided magnetic particles, surface area of which is coated with antibodies directly bonded thereto, said antibodies being specific to said select protein.
Claim 15
Dependent Claim
45 words
A diagnostic device for determining the presence or absence of select protein in a liquid sample comprising in combination a plurality of finely divided magnetic particles, surface area of which is coated with antibodies directly bonded thereto, said antibodies being specific to said select protein.
Claim 16
Dependent Claim
24 words
The diagnostic device of claim 13 wherein the magnetic particles are in the size range of from about colloidal size to about 10 microns.
Claim 17
Dependent Claim
14 words
The diagnostic device of claim 13 wherein the magnetic particles are made of nickel.
References Cited (Backward Citations)
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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) | 1980-04-18 | 1980-10-18 | 1981-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-18 | 1984-10-18 | 1985-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-18 | 1988-10-18 | 1989-04-19 | $7700.00 | Window Closed / Lapsed |