Figure 4.

Effects of various metal ions on ability of hyaluronic acid (HA) to inhibit the activity of antithrombin (AT). HA (1000 μg/ml) and antithrombin (150 μg/ml) were incubated with various concentrations of CaCl₂, FeCl₃, KCl, MgCl₂, or NaCl. Thrombin activity of blank (reaction buffer only) was considered as 1 and the activities of other tests were normalized based on comparisons with blank. Values are expressed as mean ± standard deviation of data from triplicate experiments.