Computer program for making measurements of accumulations of magnetic particles

• US 6,483,303 B2
• Filed: 07/23/2001
• Issued: 11/19/2002
• Est. Priority Date: 11/21/1997
• Status: Expired due to Term

• Current Assignee: Quantum Design International, Inc.
• Original Assignee: Quantum Design, Inc.
• Inventors: Diederichs, Jost Hermann, Jensen, Kurt Gordon, Black, Randall Christopher, Simmonds, Michael Bancroft
• Primary Examiner(s): PATIDAR, JAY M
• Application Number:
  US09/911,939
• Publication Number:
  US 20010052770A1
• Time in Patent Office: 484 Days
• Field of Search: 324/201, 324/204, 324/233, 324/234, 324/236, 324/239, 324/243, 324/226, 324/71.1, 324/71.4, 702/19, 702/21, 702/26, 702/29, 702/38, 422/68.1, 436/526
• US Class Current: 324/239
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: G01N 27/745 for detecting magnetic beads used in biochemical assays concerning the assays G01N33/54326; sensors therefor G01R33/1269; automatic analysers therefor G01N35/0098
• CPC Class Codes: G01N 35/0098 involving analyte bound to insoluble magnetic carrier, e.g. using magnetic separation magnetic particles used in immunoassays G01N33/54326; magnetic separation in general B03C
• CPC Class Codes: G01R 33/12 Measuring magnetic properties of articles or specimens of solids or fluids involving magnetic resonance G01R33/20
• CPC Class Codes: Y10S 977/773 Nanoparticle, i.e. structure having three dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/838 Magnetic property of nanomaterial
• CPC Class Codes: Y10S 977/96 Of magnetic property

Abstract

An apparatus is provided for quantitatively measuring groups of magnetic particles. The particles are complexed with substances to be determined and are excited in a magnetic field. The magnetizations of the magnetic particles are thereby caused to oscillate at the excitation frequency in the manner of a dipole to create their own fields. These fields are inductively coupled to at least one sensor such as sensing coils fabricated in a gradiometer configuration. The output signals from the sensing coils are appropriately amplified and processed to provide useful output indications.

Claims

1. A computer program, residing on a computer-readable medium, for quantitatively measuring analyte particles combined with magnetically susceptible particles which form bound complex samples, the computer program comprising instructions for causing an apparatus to:

create a magnetic field;

excite the magnetically susceptible particles, that are bound with analyte particles and which form bound complex samples, and cause oscillations of the magnetizations therein;

sense the fields generated by the oscillating magnetizations; and

create a signal representative of the sensed fields.