Patent ID: 6165795
Filing Date: 2000-12-26
Classification: G01N,Y10T

Abstract:
A method of performing a fibrinogen assay, comprising:(i) subjecting to an oscillating magnetic field a reaction slide bearing (1) a sample well for receiving a liquid sample and (2) a reaction chamber containing a dry reagent matrix comprising ecarin in which is embedded a plurality of magnetic particles distributed homogeneously therethrough;said sample well and reaction chamber being in fluid connection through a transport zone of geometry such that a volume of liquid analyte sample placed in said sample well and corresponding to the volume of said reaction chamber is transported from said sample well to said reaction chamber;(ii) under conditions suitable for conducting a fibrinogen assay, adding a whole blood or a blood-derived sample to said sample well whereby said sample is introduced into said reaction chamber, said reagent is solubilized and said particles are freed to move in an oscillating pattern induced by said oscillating magnetic field, wherein said oscillating pattern has a start time and a stop time, corresponding to a change in the degree of particle movement relative to said oscillating magnetic field;(iii) optically monitoring said reaction chamber to provide a particle oscillation curve and to measure one or more of the following parameters (iiia) said start time and said stop time for said fibrinogen assay, or (iiib) a maximum amplitude of said particle oscillation, A, and a subsequent residual, post peak minimum amplitude, B, of said particle oscillation, or (iiic) a slope of said particle oscillation curve or area defined by said curve in the region between A and B; and(iv) using said start time and said stop time, or at least B, or said slope, or said area to correlate at least one of said parameters (iiia)-(iiic) to the concentration of clottable fibrinogen in standard samples to measure the concentration of clottable fibrinogen in said whole blood or blood-derived sample.