Optical quantification of analytes in membranes

• US 6,165,798 A
• Filed: 10/10/1996
• Issued: 12/26/2000
• Est. Priority Date: 10/10/1996
• Status: Expired due to Fees

• Current Assignee: British Columbia Cancer Agency Branch (Province of British Columbia)
• Original Assignee: University of British Columbia
• Inventors: Brooks, Donald Elliott
• Primary Examiner(s): LUDLOW, JAN M
• Application Number:
  US08/727,998
• Time in Patent Office: 1,538 Days
• Field of Search: 436/164, 436/169, 436/172, 436/175, 436/183, 436/178, 436/530, 436/533
• US Class Current: 436/169
• CPC Class Codes: G01N 33/54306 Solid-phase reaction mechanisms
• CPC Class Codes: G01N 33/54393 Improving reaction conditions or stability, e.g. by coating or irradiation of surface, by reduction of non-specific binding, by promotion of specific binding
• CPC Class Codes: Y10T 436/25125 Digestion or removing interfering materials

Abstract

Methods for measuring the amount of an analyte in a membrane, by applying to the membrane a clearing agent, are disclosed. The clearing agent can be an agent that has approximately the same refractive index as the membrane; alternatively, the clearing agent can be a dissolving agent, that dissolves the membrane. The analyte can be labelled to facilitate detection. Representative labels include fluorescent labels and detectable particles.

Claims

1. A method of measuring the amount of an analyte of interest in a membrane, comprising the steps of:

a. applying to the membrane a clearing agent that is a dissolving agent selected from the group consisting of;

a low molecular weight polymer and a mixture of low molecular weight polymers, wherein the clearing agent is an agent that causes the membrane to become transparent, such that light passes through the membrane with little or no scattering caused by the substance of the membrane;

that does not dissolve the analyte or interfere with any label; and

that does not significantly displace the analyte from its position on the membrane;

b. maintaining the membrane under conditions sufficient to allow clearing of the membrane; and

c. measuring the amount of the analyte using an optical sensor.

2. The method of claim 1, wherein the membrane is nitrocellulose.

3. The method of claim 2, wherein the dissolving agent is a polyethylene glycol.

4. The method of claim 1, wherein the analyte is labelled.

5. The method of claim 4, wherein the label is a fluorescent label.

6. The method of claim 5, wherein the optical sensor measures intensity of fluorescence.

7. The method of claim 4, wherein the label is a detectable particle.

8. The method of claim 7, wherein the detectable particle is fluorescently labeled.

9. The method of claim 7, wherein the particle is a latex bead.

10. The method of claim 7, wherein the optical sensor measures intensity of scattered light.