Capillary-fill biosensor device comprising a calibration zone

• US 6,027,944 A
• Filed: 12/24/1997
• Issued: 02/22/2000
• Est. Priority Date: 11/22/1990
• Status: Expired due to Fees

• Current Assignee: Laboratoires Serono SA
• Original Assignee: Applied Research Systems ARS Holding NV (Merck & Co., Inc.)
• Inventors: Robinson, Grenville Arthur, Attridge, John Worthington, Daniels, Phelim Brinley, Thomson, Aileen Margaret, Love, Colin Andrew, Deacon, Julie Karen
• Primary Examiner(s): Chin, Christopher L.
• Assistant Examiner(s): PORTNER, VIRGINIA ALLEN
• Application Number:
  US08/998,185
• Time in Patent Office: 790 Days
• Field of Search: 436/514, 436/518, 436/527, 436/529, 436/808, 435/7.1, 435/967, 435/968, 435/975, 435/7.92, 435/7.93, 435/7.94, 435/7.95, 422/56, 422/57, 422/82.07, 422/82.08, 422/82.11
• US Class Current: 436/518
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• CPC Class Codes: Y10S 435/967 Standards, controls, materials, e.g. validation studies, buffer systems

Abstract

A method of assay for a ligand in a sample is described in which calibration occurs within the assay. This is achieved utilizing a measurement region and one or more calibration regions. In at least one of the calibration regions a non-zero signal results, either because of the presence of a calibration reagent or as a result of a binding reaction analogous to that which takes place in the measurement region.

Claims

1. A capillary-fill biosensor device suitable for use in assaying a ligand in a liquid sample, said device comprising (1) a measurement zone, (2) least one spatially distinct calibration zone and (3) at least one spatially distinct auxiliary calibration zone wherein

(1) the measurement zone comprises (a) a known amount of a releasable first ancillary specific binding reagent and (b) a measurement surface comprising an immobilized measurement specific binding reagent capable of specifically binding with at least one of the ligand, the first ancillary specific binding reagent, or a first binding partner which specifically binds to said ligand and said first ancillary specific binding reagent;

wherein the first ancillary specific binding reagent is provided either on a surface of the measurement zone separate from the measurement surface or prebound to said immobilized measurement specific binding partner or reagent,

(2) the calibration zone comprises (c) a known amount of at least one releasable second ancillary specific binding reagent and a calibration surface comprising an immobilized calibration specific binding reagent having binding sites identical in structure to those of the immobilized measurement specific binding reagent and capable of specifically binding with at least one of the ligand, the second ancillary specific binding partner and a second binding partner which specifically binds to said ligand and said second ancillary specific binding reagent, and

(3) the auxiliary calibration zone comprises an auxiliary calibration surface comprising an immobilized first auxiliary calibration binding reagent or an immobilized first auxiliary calibration reagent capable of giving rise to a zero or non-zero signal without the need for the presence of an ancillary reagent;

wherein the releasable reagents remain in their respective zones without mixing with each other in the assay following either sequential or simultaneous contact with the liquid sample to provide (a) a specific binding complex immobilized on the measurement surface which is correlative of the presence or amount of the ligand in the liquid sample, (b) a calibration specific binding complex immobilized on the calibration surface as a result of an identical specific binding reaction as occurs on the measurement surface so as to provide a measurement correlative of a known amount of said ligand, and, optionally, (c) a nonspecific binding complex immobilized on the auxiliary calibration zone to provide a measurement for correcting nonspecific background binding.

2. The capillary-fill biosensor device as claimed in claim 1, wherein the auxiliary calibration zone comprises:

(d) either a known amount of a releasable third ancillary specific binding reagent and a first auxiliary calibration surface comprising an immobilized first auxiliary calibration specific binding reagent having binding sites identical in structure to those of the immobilized measurement specific binding reagent and capable of specifically binding to at least one of an unknown amount of the ligand, a known amount of the ligand, and the third ancillary specific binding reagent, or

(e) a first auxiliary calibration surface comprising an immobilized first auxiliary calibration nonspecific binding reagent,

wherein the third ancillary specific binding reagent is provided wither on a surface of the first auxiliary calibration zone separate from the first auxiliary calibration surface or prebound to the immobilized first auxiliary calibration specific binding reagent, and is (i) an optionally labelled specific binding partner for said ligand, (ii) a labelled ligand analogue, (iii) a combination of the ligand analogue and specific binding partner for the ligand, (iv) a known amount of the ligand prebound to said specific binding partner for said ligand, (v) an optionally labelled nonspecific binding ligand which binds to the immobilizes first auxiliary calibration nonspecific binding reagent, or (vi) a combination of said nonspecific binding ligand and an optionally labelled nonspecific binding reagent therefore.

3. The device as claimed in claim 2, wherein said measurement, calibration and auxiliary calibration zones are provided as a transparent capillary comprising an upper portion and a lower portion, wherein the releasable reagents are provided on an inner surface of said upper portion and the measurement, calibration and auxiliary calibration surfaces are provided on a inner surface of said bottom portion, said transparent capillary being a light-transmissive wave guide.

4. The device as claimed in claim 1, further comprising a detection means for measuring the specific binding complex immobilized on the measurement surface, the calibration specific binding complex immobilized on the calibration surface and, optionally, the nonspecific binding complex immobilized on the auxiliary calibration zone.

5. The device as claimed in claim 4, wherein the detection means is a fluorescence monitor, the releasable reagents are labelled with a fluorogenic label, and wherein the device further comprises a radiation source for exciting said fluorogenic label.

6. The device as claimed in claim 1, wherein the first auxiliary calibration zone comprises:

(e) either a known amount of releasable third ancillary specific binding reagent and a first auxiliary calibration surface comprising an immobilized first auxiliary calibration specific binding reagent having binding sites identical in structure to those of the immobilized measurement specific binding reagent and capable of specifically binding to at least one of the ligand and the third ancillary specific binding reagent, or

(f) a first auxiliary calibration surface comprising an immobilized first auxiliary calibration nonspecific binding reagent,

wherein the third ancillary specific binding reagent is provided either on a surface of the first auxiliary calibration zone separate from the first auxiliary calibration surface or prebound to the immobilized first auxiliary calibration specific binding reagent, and is (i) said labelled ligand analogue or (ii) said combination of the labelled ligand analogue and specific binding partner for the ligand or (iii) an optionally labelled nonspecific binding ligand which binds to the immobilized first auxiliary calibration nonspecific binding reagent.

7. The device as claimed in claim 1, wherein the auxiliary calibration zone comprises:

(e) either a known amount of at least one releasable third ancillary specific binding reagent and a first auxiliary calibration surface comprising an immobilized first auxiliary calibration specific binding reagent having binding sites identical in structure to those of the immobilized measurement specific binding reagent and capable of specifically binding to at least one of the ligand and the third ancillary specific binding reagents, or

(f) a first auxiliary calibration surface comprising an immobilized first auxiliary nonspecific binding reagent,

wherein the third ancillary specific binding reagent is provided wither on a surface of the first auxiliary calibration zone separate from the first auxiliary calibration surface or prebound to the immobilized first auxiliary calibration specific binding reagent, and is (i) said ligand analogue or (ii) said specific binding partner for the ligand or (iii) a nonspecific binding ligand which binds to the immobilized first auxiliary nonspecific binding reagent.

8. The device as claimed in claim 1, wherein the first auxiliary calibration zone comprises:

(e) either a known amount of a releasable third ancillary specific binding reagent and a first auxiliary calibration surface comprising an immobilized first auxiliary calibration specific binding reagent having binding sites identical in structure to those of the immobilized measurement specific binding reagent and capable of specifically binding to at least one of an unknown amount of the ligand, a known amount of the ligand, and the third ancillary specific binding reagent, or

(f) a first auxiliary calibration surface comprising an immobilized first auxiliary calibration nonspecific binding reagent,

wherein the third ancillary specific binding reagent is provided either on a surface of the first auxiliary calibration zone separate from the first auxiliary calibration surface or prebound to the immobilized first auxiliary calibration specific binding reagent, and is (i) a labelled specific binding partner for said ligand, (ii) a known amount of the ligand prebound to said specific binding partner for said ligand, (iii) an optionally labelled nonspecific binding ligand which binds to the immobilized first auxiliary calibration nonspecific binding reagent, or (iv) a combination of said nonspecific binding ligand and an optionally labelled nonspecific binding reagent therefore.

9. The device as claimed in claim 3, further comprising a layer of light-absorbing or opaque material coating an outer surface of said bottom portion of said capillary opposite the measurement, calibration and auxiliary calibration surfaces.