Self-calibration system for a magnetic binding assay

• US 20040043512A1
• Filed: 08/27/2002
• Published: 03/04/2004
• Est. Priority Date: 08/27/2002
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Song, Xuedong, Kaylor, Rosann
• Granted Patent: US 7,432,105 B2
• Time in Patent Office: Days
• US Class Current: 436/526
• CPC Class Codes: G01N 33/54326 Magnetic particles
• CPC Class Codes: G01N 33/582 with fluorescent label
• CPC Class Codes: Y10S 435/967 Standards, controls, materials, e.g. validation studies, buffer systems
• CPC Class Codes: Y10S 436/80 Fluorescent dyes, e.g. rhodamine
• CPC Class Codes: Y10S 436/905 Photochemical activation of reactions
• CPC Class Codes: Y10T 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing
• CPC Class Codes: Y10T 436/101666 Particle count or volume standard or control [e.g., platelet count standards, etc.]
• CPC Class Codes: Y10T 436/105831 Protein or peptide standard or control [e.g., hemoglobin, etc.]

Abstract

A self-calibrated, magnetic binding assay (e.g., sandwich, competitive, etc.) for detecting the presence or quantity of an analyte residing in a test sample is provided. The magnetic binding assay includes detection probes capable of generating a detection signal (e.g., fluorescent non-magnetic particles) and calibration probes capable of generating calibration signal (e.g., fluorescent magnetic particles). The amount of the analyte within the test sample is proportional to the intensity of the detection signal calibrated by the intensity of the calibration signal.

Claims

1. A self-calibrated, magnetic binding assay for detecting the presence or quantity of an analyte residing in a test sample, said magnetic binding assay comprising detection probes capable of generating a detection signal and magnetic calibration probes capable of generating a calibration signal, wherein the amount of the analyte within the test sample is proportional to the intensity of the detection signal calibrated by the intensity of the calibration signal.

2. An assay as defined in claim 1, wherein said detection probes, said calibration probes, or combinations thereof are conjugated with a specific binding member.

3. An assay as defined in claim 2, wherein said specific binding member is selected from the group consisting of antigens, haptens, aptamers, antibodies, and complexes thereof.

4. An assay as defined in claim 1, wherein said detection probes and said calibration probes are selected from the group consisting of fluorescent compounds, chemiluminescent compounds, phosphorescent compounds, and combinations thereof.

5. An assay as defined in claim 4, wherein said detection probes and said calibration probes are fluorescent compounds.

6. An assay as defined in claim 5, wherein said fluorescent compounds are particles.

7. An assay as defined in claim 1, wherein said detection probes are fluorescent non-magnetic compounds.

8. An assay as defined in claim 1, wherein said calibration probes are fluorescent magnetic particles.

9. An assay as defined in claim 8, wherein said fluorescent magnetic particles are conjugated with a specific binding member.

10. An assay as defined in claim 8, wherein said fluorescent magnetic particles are blocked.

11. An assay as defined in claim 1, wherein said detection probes are capable of binding to the analyte.

12. An assay as defined in claim 1, further comprising non-fluorescent magnetic particles.

13. An assay as defined in claim 12, wherein said non-fluorescent magnetic particles are capable of binding to the analyte.

14. An assay as defined in claim 1, wherein the amount of the analyte within the test sample is proportional to the intensity of the detection signal divided by the intensity of the calibration signal.

15. An assay as defined in claim 1, wherein the assay is a sandwich-type assay.

16. An assay as defined in claim 1, wherein the assay is a competitive-type assay.

17. A self-calibrated, magnetic binding assay for detecting the presence or quantity of an analyte residing in a test sample, said magnetic binding assay comprising fluorescent non-magnetic detection probes capable of generating a detection signal and fluorescent magnetic calibration probes capable of generating a calibration signal, wherein the amount of the analyte within the test sample is proportional to the intensity of the detection signal calibrated by the intensity of the calibration signal.

18. An assay as defined in claim 17, wherein said detection probes, said calibration probes, or combinations thereof are conjugated with a specific binding member.

19. An assay as defined in claim 17, wherein the assay is a sandwich-type assay.

20. An assay as defined in claim 19, wherein the amount of analyte within the test sample is directly proportional to the intensity of the detection signal calibrated by the intensity of the calibration signal.

21. An assay as defined in claim 17, wherein the assay is a competitive-type assay.

22. An assay as defined in claim 21, wherein the amount of analyte within the test sample is inversely proportional to the intensity of the detection signal calibrated by the intensity of the calibration signal.

23. A method for detecting the presence or quantity of an analyte residing in a test sample, said method comprising:

i) providing a magnetic binding assay comprising detection probes capable of generating a detection signal and magnetic calibration probes capable of generating a calibration signal;

ii) contacting a test sample containing the analyte with said detection probes and said calibration probes;

iii) separating said detection probes and said calibration probes from the test sample using a magnetic device;

iv) exciting said separated detection probes and said separated calibration probes, wherein the excitation causes said separated detection probes to emit the detection signal and said separated calibration probes to emit the calibration signal;

v) measuring the intensity of the detection signal and the intensity of the calibration signal; and

vi) comparing the intensity of the detection signal to the calibration signal, wherein the amount of the analyte within the test sample is proportional to the intensity of the detection signal calibrated by the intensity of the calibration signal.

24. A method as defined in claim 23, wherein said detection probes and said calibration probes are fluorescent.

25. A method as defined in claim 23, wherein said detection probes and said calibration probes are chemiluminescent.

26. A method as defined in claim 23, wherein said detection probes and said calibration probes are phosphorescent.

27. A method as defined in claim 23, wherein said detection signal is measured at a first emission wavelength.

28. A method as defined in claim 27, wherein said calibration signal is measured at a second emission wavelength.

29. A method as defined in claim 28, wherein said first emission wavelength is different than said second emission wavelength.

30. A method as defined in claim 23, wherein said detection probes are non-magnetic.

31. A method as defined in claim 23, further comprising generating a calibration curve by plotting the intensity of the detection signal calibrated by the intensity of the calibration signal for a plurality of predetermined analyte concentrations.

32. A method as defined in claim 23, wherein said assay is a sandwich-type assay.

33. A method as defined in claim 23, wherein said assay is a competitive-type assay.

34. A method as defined in claim 23, wherein said separated detection probes and said separated calibration probes are excited simultaneously.

35. A method as defined in claim 23, wherein the intensity of the detection signal and the calibration signal are measured simultaneously.