Method and Apparatus for Determining an Analyte in a Liquid Sample

• US 20090305332A1
• Filed: 06/05/2009
• Published: 12/10/2009
• Est. Priority Date: 06/05/2008
• Status: Active Grant

• Current Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Haendler, Erich, Oranth, Norbert
• Granted Patent: US 8,129,138 B2
• Time in Patent Office: Days
• US Class Current: 435/29
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/557 using kinetic measurement, i.e. time rate of progress of an antigen-antibody interaction
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387

Abstract

A method for the determination of an analyte in a liquid sample, especially a body liquid sample, with the aid of an analytical apparatus. The apparatus receives a first measuring signal s_i (i=0, 1, . . . ) and a second measuring signal s_j (j=1, 2, . . . ; j>i) for a test system with several successively arranged measuring areas through which a liquid sample with an analyte can flow after being applied on the test system are received by an evaluation apparatus comprised by the analytical apparatus, wherein the first measuring signal s_i indicates a part of the analyte bound in a first measuring area and the second measuring signal s_j indicates a part of the analyte bound in a second measuring area that is arranged downstream the first measuring area on the test system after the application of the liquid sample on the test system, a concentration measure N correlating with the concentration of the analyte in the liquid sample is determined by the evaluation apparatus in accordance with the following linkage of measuring signals:

$N=\frac{{\left(s_j\right)}^{i+2}}{\left[s_i-{\left({\left(s_i\right)}^{j-i-1}·s_j\right)}^{\frac{1}{j-i}}\right]·{\left({\left(s_i\right)}^{j-i-1}·s_j\right)}^{\frac{i}{j-1}}},\mathrm{and}$

the concentration measurement is outputted by the evaluation apparatus after a selective further processing. Furthermore, the invention relates to an analytical apparatus for the determination of an analyte in a liquid sample as well as to a computer readable medium for performing function to determine an analyte in a liquid sample.

Claims

1. A method for the determination of an analyte in a liquid sample with the aid of an analytical apparatus, the method comprising

(a) applying a liquid sample to a test system comprising several successively arranged measuring areas, and through which liquid sample can flow;

(b) measuring a first measuring signal s_i and a second measuring signal s_j wherein the first measuring signal s_i indicates a part of the analyte bound in a ith measuring area and the second measuring signal s_j indicates a part of the analyte bound in a jth measuring area that is arranged downstream the ith measuring area on the test system,

(c) calculating a concentration measure N correlating with the concentration of the analyte in the liquid sample is determined by the analytical apparatus in accordance with the following linkage of measuring signals;

$N=\frac{{\left(s_j\right)}^{i+2}}{\left[s_i-{\left({\left(s_i\right)}^{j-i-1}·<br><br>s_j\right)}^{\frac{1}{j-i}}\right]·<br><br>{\left({\left(s_i\right)}^{j-i-1}·<br><br>s_j\right)}^{\frac{i}{j-1}}}.$

2. The method of claim 1, wherein the first measuring signal is an optical signal and the second measuring signal is an optical signal.

3. The method of claim 1, wherein the ith and the jth measuring areas are adjacent areas on the test system, so that j=i+1, and the concentration measure N is determined by the analytical apparatus in accordance with the following formula:

$N=\frac{{\left(s_i\right)}^{i+2}}{\left[s_i-s_{i+1}\right]·<br><br>{\left(s_{i+1}\right)}^i}.$

9. The analytical apparatus of claim 1, wherein analytical apparatus is a test system.

4. An analytical apparatus for the determination of an analyte in a liquid sample, the apparatus being configured to receive a first measuring signal s_i and a second measuring signal s_j from a test system with several successively arranged measuring areas through which the liquid sample can flow after being applied on the test system, t, wherein the first measuring signal s_i indicates a part of the analyte bound in a ith measuring area and the second measuring signal s_j indicates a part of the analyte bound in a jth measuring area that is arranged downstream the jth measuring area, and wherein analytical apparatus further comprises an evaluation apparatus configured for determining and outputting a concentration measure N correlating with the concentration of the analyte in the liquid sample in accordance with the following formula:

$N=\frac{{\left(s_j\right)}^{i+2}}{\left[s_i-{\left({\left(s_i\right)}^{j-i-1}·<br><br>s_j\right)}^{\frac{1}{j-i}}\right]·<br><br>{\left({\left(s_i\right)}^{j-i-1}·<br><br>s_j\right)}^{\frac{i}{j-1}}}.$

5. The analytical apparatus of claim 4, wherein the evaluation apparatus is further configured to receive a first optical signal as the first measuring signal and a second optical signal as the second measuring signal.

6. The analytical apparatus of claim 4, wherein the evaluation apparatus is further configured to determine the concentration measure N in accordance with the following formula:

$N=\frac{{\left(s_i\right)}^{i+2}}{\left[s_i-s_{i+1}\right]·<br><br>{\left(s_{i+1}\right)}^i},$

when the ith and the jth measuring areas are adjacent areas on the test system, so that j=i+1.

7. The apparatus of claim 4, further comprising a detector apparatus for detecting the first and the second measuring signal and to output them to the evaluation apparatus.

8. The apparatus of claim 5, further comprising a detector apparatus that detects the first and the second optical measuring signals;

wherein the measuring signals are independently selected from the following group of signal types;

fluorescence signal, transmission signal, absorption signal and reflection signal.

10. A computer readable medium encoded with a computer program that enables an evaluation apparatus to perform functions comprising:

receiving a first measuring signal s_i and a second measuring signal s_j for a test system with several successively arranged measuring areas through which a liquid sample with an analyte can flow after being applied on the test system, wherein the ith measuring signal s_i indicates a part of the analyte bound in a first measuring area and the second measuring signal s_j indicates a part of the analyte bound in a jth measuring area that is arranged downstream the ith measuring area on the test system after the application of the liquid sample on the test system,

determining a concentration measure N correlating with the concentration of the analyte in the liquid sample in accordance with the following formula;

$N=\frac{{\left(s_j\right)}^{i+2}}{\left[s_i-{\left({\left(s_i\right)}^{j-i-1}·<br><br>s_j\right)}^{\frac{1}{j-i}}\right]·<br><br>{\left({\left(s_i\right)}^{j-i-1}·<br><br>s_j\right)}^{\frac{i}{j-1}}},\mathrm{and}$

outputting the concentration measure N.