The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 08, 2005
Filed:
Aug. 01, 2003
Antonio A. Garcia, Chandler, AZ (US);
Mark Hayes, Gilbert, AZ (US);
Anil Vuppu, Tempe, AZ (US);
Karl Booksh, Gilbert, AZ (US);
Antonio A. Garcia, Chandler, AZ (US);
Mark Hayes, Gilbert, AZ (US);
Anil Vuppu, Tempe, AZ (US);
Karl Booksh, Gilbert, AZ (US);
Arizona Board of Regents, Tempe, AZ (US);
Abstract
A method for measuring low levels of a substance in a sample includes the formation of a rotor from paramagnetic particles in a substantially uniform magnetic field. The rotor is rotated by rotating the substantially uniform magnetic field. A portion of the substance in a sample is bound to the paramagnetic particles, and a signal having a time-varying component is detected. The signal is then processed using a lock-in amplifier with a reference signal having a frequency twice that of the rotation of the magnetic field. This improves the signal-to-noise ratio of the time-varying component of the signal.