Patent ID: 6437563
Filing Date: 2002-08-20
Classification: B82Y,G01N,G01R,Y10S

Abstract:
An apparatus capable of quantitative magnetic measurement of samples, the samples each including a plurality of combinations of analytes and magnetically susceptible particles, each sample arranged in a predefined pattern and disposed in a sample holder, comprising:a magnetic field source to apply an alternating magnetic field to the sample, the magnetic field source defining a gap in which a sample holder is movably disposed; a substantially flat magnetic field sensor to sense an induced magnetic moment from the sample and configured and arranged in a gradiometer configuration to substantially eliminate the contribution of the magnetic field source to the sensing, the magnetic field sensor having a sensing area substantially the same as the extent of each sample, the magnetic field sensor having an output to communicate output signals, the magnetic field sensor disposed substantially within the gap of the magnetic field source; and an electronic signal processor to process the output signals from the magnetic field sensor to provide a signal indicative of the quantity of magnetic material in the sample.