Multi-optical detection system

• US 5,427,915 A
• Filed: 08/09/1993
• Issued: 06/27/1995
• Est. Priority Date: 06/15/1989
• Status: Expired due to Fees

• Current Assignee: Biocircuits Corporation
• Original Assignee: Biocircuits Corporation
• Inventors: Pan, Victor, Scott, John C., Guion, Todd A., Murdoch, Joseph R., Ribi, Hans O., Choate, Glenda L.
• Primary Examiner(s): Spiegel, Carol A.
• Application Number:
  US08/104,429
• Time in Patent Office: 687 Days
• Field of Search: 385/12, 422/82.05, 422/82.06, 422/82.09, 422/82.11, 435/7.1, 435/7.92-7.95, 435/174, 435/180, 435/181, 435/970, 436/527, 436/528, 436/532, 427/2
• US Class Current: 435/7.92
• CPC Class Codes: B01J 2219/00734 Lipids
• CPC Class Codes: G01N 21/23 Bi-refringence
• CPC Class Codes: G01N 33/5432 Liposomes or microcapsules
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: G01N 33/544 the carrier being organic
• CPC Class Codes: Y10S 435/97 Test strip or test slide
• CPC Class Codes: Y10S 436/805 Optical property

Abstract

Apparatus and methods are provided for the detection of analytes. A polyunsaturated polymerized lipid layer is employed, which is anisotropic, has a member of a specific binding pair bound to an end of the lipids, and whose optical characteristics are modified upon complex formation between the specific binding pair member and its complementary member. By providing for polarized light, linear and/or circular, one can detect the presence of complex formation by the change in the optical characteristics of the film. Polarizers, analyzers, and wave plates are employed for providing for a light signal which can be analyzed and related to the presence of an analyte in a sample.

Claims

1. The method for determining the presence of an analyte in a sample, employing a detection system comprising a crystalline anisotropic polymerized polyunsaturated lipid monolayer having extended conjugated aliphatic unsaturation and groups attached to one surface of said layer said surface being hydrophilic, wherein said groups are one member of a specific binding pair and said analyte is a member of said same specific binding pair, wherein specific binding of said analyte or a conjugate of a label and said analyte to said groups on said hydrophilic surface of said lipid monolayer produces a change in intensity, orientation and/or amplitude of light emanating from said lipid monolayer said method comprising:

contacting said lipid monolayer with said sample;

irradiating said lipid monolayer with collimated light; and

determining the change in intensity, orientation and/or amplitude of light emanating from said lipid monolayer as compared to an change in intensity, orientation and/or amplitude of light emanating from said lipid monolayer produced by contacting said lipid monolayer with a control sample as a determination of the presence of said analyte in said sample.

2. The method according to claim 1, wherein said collimated light is polarized light.

3. The method according to claim 2, wherein said polarized light is linear polarized light.

4. The method according to claim 1, wherein said irradiating is through said lipped monolayer.

5. The method according to claim 1, wherein said irradiating is with evanescent light and said light emanating from said lipid monolayer is fluorescent light.

6. The method according to claim 1, wherein said detection system further comprises a member of said specific binding pair conjugated to an enzyme.

7. The method according to claim 6, wherein said detection system further comprises an enzyme substrate wherein said enzyme converts said enzyme substrate to an insoluble product which precipitates on said hydrophilic surface thereby changing the intensity, orientation and/or amplitude of light emanating from said lipid monolayer.

8. The method according to claim 1, wherein said method further comprises providing a second lipid monolayer as described in claim 1 as a control lipid monolayer and the additional steps of:

contacting said control sample to said control lipid monolayer;

concurrently irradiating said control monolayer and said sample-contacted lipid monolayer with said collimated light;

determining the change in intensity, orientation and/or amplitude of light emanating from said control lipid monolayer; and

comparing said change from said control lipid monolayer with said change from said sample-contacted lipid monolayer produced by the specific binding of said analyte to said groups on said hydrophilic surface of said lipid monolayer.

9. The method or determining the presence of an analyte in a sample, employing a detection system comprising a crystalline anisotropic polymerized polyunsaturated lipid monolayer having extended conjugated aliphatic unsaturation and groups attached to one surface of said layer said surface being hydrophilic wherein said groups are one member of a specific binding pair and said analyte is a member of said same specific binding pair, wherein specific binding of said analyte or a conjugate comprising a label and said analyte to said groups on said hydrophilic surface of said lipid monolayer produces a change in the linear or circular birefringence or dichroism of light emanating from said lipid monolayer, said method comprising:

contacting said lipid monolayer with said sample in a liquid assay medium;

modulating a collimated light source with at least one of a polarizer or wave plate to produce polarized light;

irradiating said lipid monolayer with said polarized light; and

determining the change in at least one of linear or circular birefringences or dichroism of light emanating from said lipid monolayer as compared to any change in linear or circular birefringence or dichroism of light emanating from said lipid monolayer produced by contacting said lipid monolayer with said liquid assay medium as a control as a determination of the presence of said analyte in said sample.

10. The method according to claim 9, wherein said lipid monolayer comprises a sample region and a control region, and said sample region is contacted with said sample in said liquid assay medium and said control region is contacted with said liquid assay medium followed by simultaneously irradiating both regions with said polarized light;

and

wherein said determining step comprises determining any change in light emanating from each of said regions; and

comparing said change from said sample region produced by the specific binding of said analyte to said groups on said hydrophilic surface of said lipid monolayer with said change from said control region as a determination of the presence of said analyte in said sample.