US4778769A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods of electrochemical assay employing a field effect transistor
Assignee: Merck Serono SA
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Filing: 1985-03-15
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Granted: 1988-10-18
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Expires: 2005-03-15
Abstract
Abstract In its broadest aspect, the present invention provides a method of assaying a ligand in a sample which comprises contacting the sample with a predetermined quantity of a specific binding partner to the ligand, said specific binding partner being immobilized on the effective gate electrode of a field effect transistor, and determining whether (and, if desired, the extent to which) an appropriate transistor characteristic is changed as a result of complex formation between the ligand and the specific binding partner.
Inventors
- 👤 Gordon C. Forrest
- 👤 Simon J. Rattle
- 👤 Grenville A. Robinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:03
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54366; G01N33/54373; G01N33/5438; Y; Y10; Y10S; Y10S435/00; Y10S435/817; Y10S436/00; Y10S436/806; Y10S436/807
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
162 words
A method of qualitatively or quantitatively assaying a ligand selected from antigens and antibodies in a liquid sample which comprises the steps of: (a) contacting the sample with a predetermined quantity of a specific binding partner to the ligand, said specific binding partner being immobilized on an effective gate electrode of a field effect transistor, said gate electrode being spatially separate from the other components of the field effect transistor, said specific binding partner being an antibody or antigen capable of binding said ligand; and (b) determining whether a transistor characteristic selected from the group consisting of the drain current (I d ) and the gate electrode potential (V g ) is changed as a result of complex formation between said ligand and said specific binding partner, the other characteristic being maintained constant or variations therein compensated for, wherein a change in the drain current or the gate electrode potential is an indication of the presence of or quantity of said ligand.
Claim 2
Independent Claim
162 words
A method of qualitatively or quantitatively assaying a ligand selected from antigens and antibodies in a liquid sample which comprises the steps of: (a) contacting the sample with a predetermined quantity of a specific binding partner to the ligand, said specific binding partner being immobilized on an effective gate electrode of a field effect transistor, said gate electrode being spatially separate from the other components of the field effect transistor, said specific binding partner being an antibody or antigen capable of binding said ligand; and (b) determining whether a transistor characteristic selected from the group consisting of the drain current (I d ) and the gate electrode potential (V g ) is changed as a result of complex formation between said ligand and said specific binding partner, the other characteristic being maintained constant or variations therein compensated for, wherein a change in the drain current or the gate electrode potential is an indication of the presence of or quantity of said ligand.
Claim 3
Dependent Claim
31 words
A method as claimed in claim 1 wherein a transistor characteristic is changed as a result of complex formation between the ligand and the specific binding partner and is determined quantitatively.
Claim 4
Dependent Claim
36 words
A method as claimed in claim 1 or claim 2 wherein the initial rate of change of said transistor characteristic as a result of complex formation between the ligand and the specific binding partner is measured.
Claim 5
Dependent Claim
42 words
A method as claimed in claim 1 or claim 2 wherein an absolute change in said transistor characteristic is determined after the complexing reaction between the ligand and the specific-binding partner has been allowed to proceed for a controlled period of time.
Claim 6
Dependent Claim
40 words
A method as claimed in claim 1 or claim 2 wherein the drain potential V d , the pH and ionic strength of the assay medium and the temperature of the system are maintained constant or variations therein compensated for.
Claim 7
Dependent Claim
40 words
Apparatus comprising a field effect transistor having an effective gate electrode on which a specific binding partner of a ligand to be assayed is immobilized, said gate electrode being spatially separate from the other components of the field effect transistor.
Claim 8
Dependent Claim
40 words
Apparatus comprising a field effect transistor having an effective gate electrode on which a specific binding partner of a ligand to be assayed is immobilized, said gate electrode being spatially separate from the other components of the field effect transistor.
Claim 9
Dependent Claim
18 words
Apparatus as claimed in claim 6 wherein the said effective gate electrode is a titanium dioxide gate electrode.
Claim 10
Dependent Claim
31 words
Apparatus as claimed in claim 6 or claim 7 wherein said effective gate electrode is covered with a membrane which is either permeable to, or perm-selective for, the ligand under assay.
Claim 11
Dependent Claim
11 words
Apparatus as claimed in claim 6 which includes a reference electrode.
Claim 12
Dependent Claim
37 words
An apparatus as claimed in claim 9 wherein at least one of the effective gate electrode and the reference electrode is covered with a membrane which is either permeable to, or perm-selective for, the ligand under assay.
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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) | 1991-10-18 | 1992-04-18 | 1992-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-18 | 1996-04-18 | 1996-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-18 | 2000-04-18 | 2000-10-18 | $7700.00 | Window Closed / Lapsed |