Development and analytical performance of a functional assay for fibrinogen on the Du Pont aca analyzer

A method for determination of functional fibrinogen has been developed for the Du Pont aca discrete clinical analyzer. This fully automated assay is based on the rate of fibrin turbidity formation when thrombin is added to the test sample. The rate of this reaction is enhanced by added calcium chloride and dextran. The assay range is from 0.50 to 8.00 g/L. Within-run reproducibility studies at the medical decision level of 1.0 g/L showed a CV of 2.5%. There was no interference by heparin up to 10 USP units per milliliter of plasma.