Patent US4727019A successfully refreshed from Google Patents.
US4727019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for immunoassays
Assignee: Hybritech Inc
•
Filing: 1985-05-10
•
Granted: 1988-02-23
•
Expires: 2005-05-10
Abstract
Abstract Disclosed herein is an apparatus and process for conducting ligand receptor assays. The apparatus comprises a first member which is a membrane or a filter to which is bound a receptor for the ligand or which is capable of extracting cells carrying the ligand from a fluid sample. The apparatus further comprises a second member which is composed of absorbent material which acts when in contact with the first member to induce flow through the first member when a fluid sample is added to it. The apparatus is used to conduct assays by applying a sample to the upper surface of the first member to bind ligand in the sample by means of receptor fixed to the first member or, in certain cases, by extracting cellular material which has ligand associated with it. Addition of the sample is typically followed by addition of labeled antibody against the antigen being assayed followed by a washing step to remove unbound labeled receptor. The presence of labeled antibody on the first member after washing is indicative of the presence of the antigen in the sample being assayed. In a preferred embodiment of the invention, the ligand is an antigen and the receptor is an antibody.
Inventors
- 👤 Gunars E. Valkirs
- 👤 Newton C. Owen
- 👤 Philip A. Levinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:28
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/5302; G01N33/543; G01N33/54366; Y; Y10; Y10S; Y10S435/00; Y10S435/805; Y10S435/974; Y10S436/00; Y10S436/807; Y10S436/815; Y10S436/817; Y10S436/818; Y10S436/82; Y10S436/824
Claims Analysis
Total Claims: 142
Claim 1
Independent Claim
176 words
An apparatus for use in a ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample comprising: (a) a porous first member which has upper and lower surfaces, the sample being applied to the upper surface, and wherein at least one first receptor capable of binding the target ligand is directly or indirectly bound within an area smaller than the area of the member to which the sample is applied; and (b) a second member which is a body of absorbent material having a surface over which the lower surface of the first member is placed and having capillaries therethrough which are in communication with the pores on the lower surface of the first member so as to draw liquid added to the upper surface of the first member which has permeated the first member into the capillaries of the second member, the communication between the first and second members having been established prior to, and maintained during, addition of liquids to the apparatus during the assay process.
Claim 2
Independent Claim
176 words
An apparatus for use in a ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample comprising: (a) a porous first member which has upper and lower surfaces, the sample being applied to the upper surface, and wherein at least one first receptor capable of binding the target ligand is directly or indirectly bound within an area smaller than the area of the member to which the sample is applied; and (b) a second member which is a body of absorbent material having a surface over which the lower surface of the first member is placed and having capillaries therethrough which are in communication with the pores on the lower surface of the first member so as to draw liquid added to the upper surface of the first member which has permeated the first member into the capillaries of the second member, the communication between the first and second members having been established prior to, and maintained during, addition of liquids to the apparatus during the assay process.
Claim 3
Dependent Claim
24 words
An apparatus according to claim 1 wherein the target ligand is selected from the group consisting of antigens, antibodies, enzymes, and nucleic acid oligomers.
Claim 4
Dependent Claim
25 words
An apparatus according to claim 2 wherein the first receptor is selected from the group consisting of antibodies, antigens, enzyme receptors, and nucleic acid oligomers.
Claim 5
Dependent Claim
16 words
An apparatus according to claim 1 wherein the porous first member is a membrane or filter.
Claim 6
Dependent Claim
20 words
An apparatus according to claim 4 wherein the membrane or filter is of a material selected from glass or nylon.
Claim 7
Dependent Claim
20 words
An apparatus according to claim 4 wherein the first and second members are separated by at least one porous member.
Claim 8
Dependent Claim
34 words
An apparatus according to claim 4 wherein the apparatus further comprises a container for the first and second members having an opening sufficient to permit the application of assay reagents to the first member.
Claim 9
Dependent Claim
33 words
An apparatus according to claim 7 wherein the opening further comprises a section having sides which slope inwardly to define a funnel for direction of the assay reagents applied to the first member.
Claim 10
Dependent Claim
48 words
An apparatus according to claim 7 wherein the bottom end of the container is closed and the container is of a volume sufficient to contain all of the assay reagents applied to the first member during the assay, the container being vented to allow escape of displaced air.
Claim 11
Dependent Claim
11 words
An apparatus according to claim 9 wherein the apparatus is disposable.
Claim 12
Dependent Claim
42 words
An apparatus according to claim 9 wherein a signal is generated to indicate the presence or concentration of the target ligand following the application of the assay reagents to the first member, the signal being either visual or determined by instrumental means.
Claim 13
Dependent Claim
11 words
An apparatus according to claim 11 wherein the signal is visual.
Claim 14
Dependent Claim
26 words
An apparatus according to claim 11 wherein the signal is generated within about five minutes following the application of the assay reagents to the first member.
Claim 15
Dependent Claim
11 words
An apparatus according to claim 13 wherein the signal is visual.
Claim 16
Dependent Claim
15 words
An apparatus according to claim 1 wherein the assay is a nucleic acid probe assay.
Claim 17
Dependent Claim
15 words
An apparatus according to claim 15 wherein the first receptor is a nucleic acid oligomer.
Claim 18
Dependent Claim
15 words
An apparatus according to claim 16 wherein the nucleic acid oligomer is a DNA oligomer.
Claim 19
Dependent Claim
12 words
An apparatus according to claim 1 wherein the assay is an immunoassay.
Claim 20
Dependent Claim
13 words
An apparatus according to claim 18 wherein the first receptor is an antibody.
Claim 21
Dependent Claim
14 words
An apparatus according to claim 19 wherein the antibody is a polyclonal antibody preparation.
Claim 22
Dependent Claim
13 words
An apparatus according to claim 19 wherein the antibody is a monoclonal antibody.
Claim 23
Dependent Claim
13 words
An apparatus according to claim 18 wherein the first receptor is an antigen.
Claim 24
Dependent Claim
13 words
An apparatus according to claim 20 wherein the target ligand is human choriogonadotropin.
Claim 25
Dependent Claim
13 words
An apparatus according to claim 21 wherein the target ligand is human choriogonadotropin.
Claim 26
Dependent Claim
21 words
An apparatus according to claim 20 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 27
Dependent Claim
21 words
An apparatus according to claim 21 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 28
Dependent Claim
19 words
An apparatus according to claim 18 wherein the target ligand is an antigen or antibody associated with a virus.
Claim 29
Dependent Claim
13 words
An apparatus according to claim 27 wherein the virus is a hepatitis virus.
Claim 30
Dependent Claim
13 words
An apparatus according to claim 27 wherein the virus is associated with AIDS.
Claim 31
Dependent Claim
111 words
A ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample employing the apparatus of claim 1 comprising: (a) applying the liquid sample suspected of containing the target ligand to the upper surface of the porous first member of the apparatus; (b) applying to the upper surface a second receptor capable of binding the target ligand, the second receptor being labeled to permit its detection; (c) separating unbound labeled second receptor from any labeled second receptor bound to the target ligand within the first member; and (d) determining the presence or concentration of the target ligand by detection of bound labeled second receptor.
Claim 32
Dependent Claim
119 words
A ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample employing the apparatus of claim 1 comprising: (a) mixing the liquid sample suspected of containing the target ligand with a second receptor capable of binding the target ligand, the second receptor being labeled to permit its detection; (b) applying the mixture of the liquid sample and the labeled second receptor to the upper surface of the porous first member of the apparatus; (c) separating unbound labeled second receptor from any labeled second receptor bound to the target ligand within the first member; and (d) determining the presence or concentration of the target ligand by detection of bound labeled second receptor.
Claim 33
Dependent Claim
26 words
A process according to claims 30 or 31 wherein the target ligand is selected from the group consisting of antigens, antibodies, enzymes, and nucleic acid oligomers.
Claim 34
Dependent Claim
25 words
A process according to claim 32 wherein the first receptor is selected from the group consisting of antibodies, antigens, enzyme receptors and nucleic acid oligomers.
Claim 35
Dependent Claim
23 words
A process according to claims 30 or 31 wherein separation of unbound second labeled receptor from the first member is accomplished by washing.
Claim 36
Dependent Claim
54 words
A process according to claim 34 wherein the second labeled receptor is labeled with an enzyme and the washing step is followed by application to the first member of a substrate for the enzyme, the enzyme and substrate being selected to generate a color change which is either visual or determined by instrumental means.
Claim 37
Dependent Claim
12 words
A process according to claim 35 wherein the color change is visual.
Claim 38
Dependent Claim
17 words
A process according to claims 30 or 31 wherein the assay is a nucleic acid probe assay.
Claim 39
Dependent Claim
26 words
A process according to claim 37 wherein the target ligand is a nucleic acid oligomer and the first and second receptors are complementary nucleic acid oligomers.
Claim 40
Dependent Claim
15 words
A process according to claim 38 wherein the first and second receptors are DNA oligomers.
Claim 41
Dependent Claim
14 words
A process according to claim 39 wherein the target ligand is a DNA oligomer.
Claim 42
Dependent Claim
14 words
A process according to claim 39 wherein the target ligand is an RNA oligomer.
Claim 43
Dependent Claim
14 words
A process according to claims 30 or 31 wherein the assay is an immunoassay.
Claim 44
Dependent Claim
21 words
A process according to claim 42 wherein the target ligand is an antigen and the first and second receptors are antibodies.
Claim 45
Dependent Claim
18 words
A process according to claim 43 wherein at least one of the antibodies is a polyclonal antibody preparation.
Claim 46
Dependent Claim
17 words
A process according to claim 43 wherein at least one of the antibodies is a monoclonal antibody.
Claim 47
Dependent Claim
24 words
A process according to claim 45 wherein the first and second antibodies are monoclonal antibodies which bind, respectively, to non-interfering epitopes of the antigen.
Claim 48
Dependent Claim
26 words
A process according to claim 42 wherein the target ligand is an antibody and at least one of the first and second receptors is an antigen.
Claim 49
Dependent Claim
30 words
A process according to claim 47 wherein the target ligand is an antibody, the first receptor is an antigen, and the second receptor is an antibody against the target antibody.
Claim 50
Dependent Claim
20 words
A process according to claim 48 wherein the antigen is an allergen and the target antibody is an IgE antibody.
Claim 51
Dependent Claim
18 words
A process according to claim 49 wherein the antibody against the IgE antibody is an anti-IgE monoclonal antibody.
Claim 52
Dependent Claim
13 words
A process according to claim 44 wherein the target ligand is human choriogonadotropin.
Claim 53
Dependent Claim
13 words
A process according to claim 45 wherein the target ligand is human choriogonadotropin.
Claim 54
Dependent Claim
13 words
A process according to claim 46 wherein the target ligand is human choriogonadotropin.
Claim 55
Dependent Claim
21 words
A process according to claim 44 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 56
Dependent Claim
21 words
A process according to claim 45 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 57
Dependent Claim
21 words
A process according to claim 46 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 58
Dependent Claim
19 words
A process according to claim 42 wherein the target ligand is an antigen or antibody associated with a virus.
Claim 59
Dependent Claim
13 words
A process according to claim 57 wherein the virus is a hepatitis virus.
Claim 60
Dependent Claim
13 words
A process according to claim 57 wherein the virus is associated with AIDS.
Claim 61
Dependent Claim
18 words
A process according to claim 42 wherein the liquid sample is urine, serum, plasma, or other liquid media.
Claim 62
Independent Claim
185 words
An apparatus for use in a ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample comprising: (a) a porous first member which has upper and lower surfaces, the sample being applied to the upper surface, and wherein at least one anti-receptor capable of binding a first receptor is directly or indirectly bound within an area smaller than the area of the member to which the sample is applied, the first receptor being capable of binding the target ligand; and (b) a second member which is a body of absorbent material having a surface over which the lower surface of the first member is placed and having capillaries therethrough which are in communication with the pores on the lower surface of the first member so as to draw liquid added to the upper surface of the first member which has permeated the first member into the capillaries of the second member, the communication between the first and second members having been established prior to, and maintained during, addition of liquids to the apparatus during the assay process.
Claim 63
Independent Claim
185 words
An apparatus for use in a ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample comprising: (a) a porous first member which has upper and lower surfaces, the sample being applied to the upper surface, and wherein at least one anti-receptor capable of binding a first receptor is directly or indirectly bound within an area smaller than the area of the member to which the sample is applied, the first receptor being capable of binding the target ligand; and (b) a second member which is a body of absorbent material having a surface over which the lower surface of the first member is placed and having capillaries therethrough which are in communication with the pores on the lower surface of the first member so as to draw liquid added to the upper surface of the first member which has permeated the first member into the capillaries of the second member, the communication between the first and second members having been established prior to, and maintained during, addition of liquids to the apparatus during the assay process.
Claim 64
Dependent Claim
24 words
An apparatus according to claim 61 wherein the target ligand is selected from the group consisting of antigens, antibodies, enzymes, and nucleic acid oligomers.
Claim 65
Dependent Claim
25 words
An apparatus according to claim 62 wherein the first receptor is selected from the group consisting of antibodies, antigens, enzyme receptors, and nucleic acid oligomers.
Claim 66
Dependent Claim
16 words
An apparatus according to claim 61 wherein the porous first member is a membrane or filter.
Claim 67
Dependent Claim
20 words
An apparatus according to claim 64 wherein the membrane or filter is of a material selected from glass or nylon.
Claim 68
Dependent Claim
20 words
An apparatus according to claim 64 wherein the first and second members are separated by at least one porous member.
Claim 69
Dependent Claim
34 words
An apparatus according to claim 64 wherein the apparatus further comprises a container for the first and second members having an opening sufficient to permit the application of assay reagents to the first member.
Claim 70
Dependent Claim
33 words
An apparatus according to claim 67 wherein the opening further comprises a section having sides which slope inwardly to define a funnel for direction of the assay reagents applied to the first member.
Claim 71
Dependent Claim
48 words
An apparatus according to claim 67 wherein the bottom end of the container is closed and the container is of a volume sufficient to contain all of the assay reagents applied to the first member during the assay, the container being vented to allow escape of displaced air.
Claim 72
Dependent Claim
11 words
An apparatus according to claim 69 wherein the apparatus is disposable.
Claim 73
Dependent Claim
42 words
An apparatus according to claim 69 wherein a signal is generated to indicate the presence or concentration of the target ligand following the application of the assay reagents to the first member, the signal being either visual or determined by instrumental means.
Claim 74
Dependent Claim
11 words
An apparatus according to claim 71 wherein the signal is visual.
Claim 75
Dependent Claim
26 words
An apparatus according to claim 71 wherein the signal is generated within about five minutes following the application of the assay reagents to the first member.
Claim 76
Dependent Claim
11 words
An apparatus according to claim 73 wherein the signal is visual.
Claim 77
Dependent Claim
15 words
An apparatus according to claim 61 wherein the assay is a nucleic acid probe assay.
Claim 78
Dependent Claim
15 words
An apparatus according to claim 75 wherein the first receptor is a nucleic acid oligomer.
Claim 79
Dependent Claim
15 words
An apparatus according to claim 76 wherein the nucleic acid oligomer is a DNA oligomer.
Claim 80
Dependent Claim
12 words
An apparatus according to claim 61 wherein the assay is an immunoassay.
Claim 81
Dependent Claim
13 words
An apparatus according to claim 78 wherein the first receptor is an antibody.
Claim 82
Dependent Claim
14 words
An apparatus according to claim 79 wherein the antibody is a polyclonal antibody preparation.
Claim 83
Dependent Claim
13 words
An apparatus according to claim 79 wherein the antibody is a monoclonal antibody.
Claim 84
Dependent Claim
13 words
An apparatus according to claim 78 wherein the first receptor is an antigen.
Claim 85
Dependent Claim
13 words
An apparatus according to claim 80 wherein the target ligand is human choriogonadotropin.
Claim 86
Dependent Claim
13 words
An apparatus according to claim 81 wherein the target ligand is human choriogonadotropin.
Claim 87
Dependent Claim
20 words
An apparatus according to claim 80 wherein the target ligand is an antigen associated with group A or group streptococcus.
Claim 88
Dependent Claim
20 words
An apparatus according to claim 81 wherein the target ligand is an antigen associated with group A or group streptococcus.
Claim 89
Dependent Claim
19 words
An apparatus according to claim 78 wherein the target ligand is an antigen or antibody associated with a virus.
Claim 90
Dependent Claim
13 words
An apparatus according to claim 87 wherein the virus is a hepatitis virus.
Claim 91
Dependent Claim
13 words
An apparatus according to claim 87 wherein the virus is associated with AIDS.
Claim 92
Dependent Claim
23 words
An apparatus according to claim 78 wherein the first receptor is an antibody and the anti-receptor is an antibody against the first receptor.
Claim 93
Dependent Claim
18 words
An apparatus according to claim 90 wherein at least one of the antibodies is a polyclonal antibody preparation.
Claim 94
Dependent Claim
17 words
An apparatus according to claim 90 wherein at least one of the antibodies is a monoclonal antibody.
Claim 95
Dependent Claim
14 words
An apparatus according to claim 92 wherein the first receptor is a monoclonal antibody.
Claim 96
Dependent Claim
13 words
An apparatus according to claim 92 wherein the anti-receptor is a monoclonal antibody.
Claim 97
Dependent Claim
24 words
An apparatus according to claim 78 wherein the first receptor is conjugated with a hapten and the anti-receptor is an antibody against the hapten.
Claim 98
Dependent Claim
11 words
An apparatus according to claim 78 wherein the hapten is fluorescein.
Claim 99
Dependent Claim
19 words
An apparatus according to claim 78 wherein the first receptor is conjugated to biotin and the anti-receptor is avidin.
Claim 100
Dependent Claim
121 words
A ligand-receptor asasy process for determination of the presence or concentration of a target ligand in a liquid sample employing the apparatus of claim 61 comprising: (a) applying the first receptor capable of binding the target ligand and the liquid sample suspected of containing the target ligand to the upper surface of the porous first member of the apparatus; (b) applying to the upper surface a second receptor capable of binding the target ligand, the second receptor being labeled to permit its detection; (c) separating unbound labeled second receptor from any labeled second receptor bound to the target ligand within the first member; and (d) determining the presence or concentration of the target ligand by detection of bound labeled second receptor.
Claim 101
Dependent Claim
142 words
A ligand-receptor assay process for determination of the presence or concentration of a target ligand in a liquid sample employing the apparatus of claim 61 comprising: (a) applying the first receptor capable of binding the target ligand to the upper surface of the porous first member of the apparatus; (b) mixing the liquid sample suspected of containing the target ligand with a second receptor capable of binding the target ligand, the second receptor being labeled to permit its detection; (c) applying the mixture of the liquid sample and the labeled second receptor to the upper surface of the porous first member of the apparatus; (d) separating unbound labeled second receptor from any labeled second receptor bound to the target ligand within the first member; and (e) determining the presence or concentration of the target ligand by detection of bound labeled second receptor.
Claim 102
Dependent Claim
26 words
A process according to claims 98 or 99 wherein the target ligand is selected from the group consisting of antigens, antibodies, enzymes, and nucleic acid oligomers.
Claim 103
Dependent Claim
25 words
A process according to claim 100 wherein the first receptor is selected from the group consisting of antibodies, antigens, enzyme receptors and nucleic acid oligomers.
Claim 104
Dependent Claim
22 words
A process according to claims 98 or 99 wherein separation of unbound labeled receptor from the first member is accomplished by washing.
Claim 105
Dependent Claim
54 words
A process according to claim 102 wherein the second labeled receptor is labeled with an enzyme and the washing step is followed by application to the first member of a substrate for the enzyme, the enzyme and substrate being selected to generate a color change which is either visual or determined by instrumental means.
Claim 106
Dependent Claim
12 words
A process according to claim 103 wherein the color change is visual.
Claim 107
Dependent Claim
17 words
A process according to claims 98 or 99 wherein the assay is a nucleic acid probe assay.
Claim 108
Dependent Claim
26 words
A process according to claim 105 wherein the target ligand is a nucleic acid oligomer and the first and second receptors are complementary nucleic acid oligomers.
Claim 109
Dependent Claim
15 words
A process according to claim 106 wherein the first and second receptors are DNA oligomers.
Claim 110
Dependent Claim
14 words
A process according to claim 107 wherein the target ligand is a DNA oligomer.
Claim 111
Dependent Claim
14 words
A process according to claim 108 wherein the target ligand is an RNA oligomer.
Claim 112
Dependent Claim
14 words
A process according to claims 98 or 99 wherein the assay is an immunoassay.
Claim 113
Dependent Claim
21 words
A process according to claim 110 wherein the target ligand is an antigen and the first and second receptors are antibodies.
Claim 114
Dependent Claim
18 words
A process according to claim 111 wherein at least one of the antibodies is a polyclonal antibody preparation.
Claim 115
Dependent Claim
17 words
A process according to claim 111 wherein at least one of the antibodies is a monoclonal antibody.
Claim 116
Dependent Claim
24 words
An process according to claim 113 wherein the first and second antibodies are monoclonal antibodies which bind, respectively, to non-interfering epitopes of the antigen.
Claim 117
Dependent Claim
26 words
A process according to claim 110 wherein the target ligand is an antibody and at least one of the first and second receptors is an antigen.
Claim 118
Dependent Claim
30 words
A process according to claim 115 wherein the target ligand is an antibody, the first receptor is an antigen, and the second receptor is an antibody against the target antibody.
Claim 119
Dependent Claim
20 words
A process according to claim 116 wherein the antigen is an allergen and the target antibody is an IgE antibody.
Claim 120
Dependent Claim
18 words
A process according to claim 117 wherein the antibody against the IgE antibody is an anti-IgE monoclonal antibody.
Claim 121
Dependent Claim
13 words
A process according to claim 112 wherein the target ligand is human choriogonadotropin.
Claim 122
Dependent Claim
13 words
A process according to claim 113 wherein the target ligand is human choriogonadotropin.
Claim 123
Dependent Claim
13 words
A process according to claim 114 wherein the target ligand is human choriogonadotropin.
Claim 124
Dependent Claim
21 words
A process according to claim 112 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 125
Dependent Claim
21 words
A process according to claim 113 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 126
Dependent Claim
21 words
A process according to claim 114 wherein the target ligand is an antigen associated with group A or group B streptococcus.
Claim 127
Dependent Claim
19 words
A process according to claim 110 wherein the target ligand is an antigen or antibody associated with a virus.
Claim 128
Dependent Claim
13 words
A process according to claim 125 wherein the virus is a hepatitis virus.
Claim 129
Dependent Claim
13 words
A process according to claim 125 wherein the virus is associated with AIDS.
Claim 130
Dependent Claim
18 words
A process according to claim 110 wherein the liquid sample is urine, serum, plasma, or other liquid media.
Claim 131
Dependent Claim
12 words
A process according to claim 110 wherein the anti-receptor is an antibody.
Claim 132
Dependent Claim
22 words
A process according to claims 98 or 99 wherein application of the first receptor is followed by application of the liquid sample.
Claim 133
Dependent Claim
25 words
A process according to claims 98 or 99 wherein the first receptor and the liquid sample are admixed prior to application to the first member.
Claim 134
Dependent Claim
12 words
An apparatus according to claim 11 wherein the assay is an immunoassay.
Claim 135
Dependent Claim
20 words
An apparatus according to claim 132 wherein the first receptor is an antibody and the target ligand is human choriogonadotropin.
Claim 136
Dependent Claim
13 words
An apparatus according to claim 133 wherein the antibody is a monoclonal antibody.
Claim 137
Dependent Claim
25 words
An apparatus according to claim 132 wherein the first receptor is an antibody and the target ligand is an antigen associated with Group A streptococcus.
Claim 138
Dependent Claim
13 words
An apparatus according to claim 135 wherein the antibody is a monoclonal antibody.
Claim 139
Dependent Claim
12 words
A process according to claim 35 wherein the assay is an immunoassay.
Claim 140
Dependent Claim
20 words
A process according to claim 137 wherein at least one of the first and second receptors is a monoclonal antibody.
Claim 141
Dependent Claim
13 words
A process according to claim 138 wherein the target ligand is human choriogonadotropin.
Claim 142
Dependent Claim
18 words
A process accoring to claim 138 wherein the target ligand is an antigen associated with Group A streptococcus.
References Cited (Backward Citations)
US3615222A
Cited
US3811840A
Cited
US3715192A
Cited
US3645687A
Cited
US3825410A
Cited
US3888629A
Cited
US3843324A
Cited
US3966897A
Cited
US4138474A
Cited
US4039652A
Cited
US4061468A
Cited
US4168146A
Cited
US4125372A
Cited
US4180383A
Cited
US4153675A
Cited
US4053284A
Cited
US4094647A
Cited
US4200690A
Cited
US4298685A
Cited
US4193983A
Cited
US4246339A
Cited
US4235601A
Cited
US4305924A
Cited
US4391904A
Cited
US4427769A
Cited
US4376110A
Cited
US4366241A
Cited
US4366241B1
Cited
US4358535A
Cited
US4358535B1
Cited
US4425438A
Cited
US4424279A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |