Novel method for measurement of heparin anticoagulant activity using SPR

A novel method has been developed for the easy measurement of heparin's anticoagulant activity using surface plasmon resonance. The anticoagulant activity of target heparin was evaluated by measuring the competitive antithrombin III binding of analyte heparin in the solution phase and USP heparin immobilized on chip surface. Heparins, obtained from different animal sources, and low molecular weight heparins were analyzed. The results were reproducible and correlated well with the results of chromogenic assays (correlation coefficient r = 0.98 for anti-Xa and r = 0.94 for anti-IIa). This protocol provides many advantages, significantly minimizing time, cost and the complications of chromogenic assay methods.