Abstract:Thrombin antithrombin (TAT) complex is the product of coagulation and anticoagulation balance. Its detection reflects thrombin status and can be used as an auxiliary in the diagnosis of thrombotic diseases. A chemiluminescence immunoassay method was established to analyze TAT complex in human plasma samples, and its analytical performance were evaluated. The TAT complex was used as immunogen for antibody preparation. TAT measurement method was established using double antibody sandwich format. After the optimization of reaction, the bulk reagent concentrations of magnetic microparticle coated with antibody and acridinium labeled antibody were 0.20 mg/mL and 200 ng/mL, respectively, and the sample size was 50 μL. The reaction of magnetic particle coated antibody and sample were incubated for 5 min, and 5 min for subsequent reacting with acridine ester labeled antibody. There was no cross-reaction with samples containing 0.20 mg/mL prothrombin or 0.31 mg/mL antithrombin Ⅲ. Besides, there was a high correlation (R > 0.99) between this method and TAT test kit of Sysmex. A quantitative chemiluminescence immunoassay method for TAT measurement has been established, and the performance meets customer needs for clinical utility.