Self-calibrating gradient dilution in a constitutent assay and gradient dilution apparatus performed in a thin film sample

Patent metadata

Field	Value
Publication number	US-9274094-B2
Application number	US-201213550131-A
Country	US
Kind code	B2
Filing date	Jul 16, 2012
Priority date	Apr 2, 2008
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

A method and apparatus for measuring antibody titers in a thin film sample in an automated system which does not require multiple dilutions. The system provides a simple method for creating an in-situ dilution within a sample analysis chamber without the use of any precision fluid-handling components, and further, to use the same principles to provide a wide range of sample dilutions within the chamber so as to obviate the need for additional dilution steps when dealing with samples possibly containing wide ranges of analyte concentrations.

First claim

What is claimed is:

1. A method for determining the relative dilution of a solution containing a ligand which is directed against a target analyte, and a liquid sample containing the target analyte to be analyzed, which target analyte sample is miscible with said ligand solution, at least one of said solution and said sample containing a detectable sensible marker, said method comprising the steps of:
a) placing a first amount of said solution in a first area of a planar reaction chamber having a thin through thickness dimension;
b) placing a second amount of said target analyte sample in a second area of the chamber, which second area is adjacent the first area of said planar chamber, and which second amount is less than the first amount;
c) allowing or causing said solution and said sample to admix with each other until an even solution-sample mixture is created in said chamber;
d) electronically imaging or scanning said resultant solution-sample mixture in said chamber to determine sensible marker signal; and
e) electronically calculating a relative concentration or dilution of each of said solution and sample from any imaged area by measuring the concentration of any marker in said mixture in said imaged area.

2. The method of claim 1 wherein said solution contains a detectable sensible marker.

3. The method of claim 1 wherein said liquid sample contains a detectable sensible marker.

4. The method of claim 1 wherein both said solution and said liquid sample contain detectable sensible markers and wherein said sensible markers produce different detectable signals.

5. The method of claim 1 wherein said allowing or causing admixing step is performed by pumping said solution and said sample in said chamber.

6. The method of claim 1 wherein said allowing or causing admixing step is performed by baffling flow of at least one of said solution and liquid sample into said chamber.

7. The method of claim 1 wherein said chamber is less than 1 mm in thickness.

8. The method of claim 7 wherein said chamber is less than 200μ in thickness.

Assignees

• Wardlaw Stephen C
• Levine Robert A
• Abbott Point Of Care Inc

Inventors

• Wardlaw Stephen C
• Levine Robert A

Classifications

• G01N33/54386

  Analytical elements · CPC title

• G01N33/48 Primary

  Biological material, e.g. blood, urine (G01N33/02, G01N33/26, G01N33/44, G01N33/46 take precedence); Haemocytometers (counting blood corpuscules distributed over a surface by scanning the surface G06M11/02) · CPC title

• G01N21/6428

  Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" (in vivo A61B5/00; immunoassay G01N33/53) · CPC title

• G01N33/54373 Primary

  involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings · CPC title

• G01N33/5304

  Reaction vessels, e.g. agglutination plates (for solid-phase systems G01N33/543) · CPC title