The one step test for d-dimer (colloidal gold) is intended for use together with the fia8000 quantitative immunoassay analyzer (fia8000). The product employs colloidal gold immunechromatogrphy to determine d-dimer in human plasma, or whole blood specimens. Two monoclonal antibodies are employed to identify d-dimer specifically, resulting in a purplish red streak appears on the test line. The color intensity of the test line increases in proportion to the concentrations of d-dimer. Then insert test card into the fia8000 quantitative immunoassay analyzer, the concentration of d-dimer is measured quantitatively and displayed on the screen. The result can be transmitted to the lab or hospital information system.