Table 2.

Binding parameters of sulfated QAOs interacting with hFXIa.^a

Inhibitor	ΔFMAX (%)	n	KD (μM)
2S	−34±1.8b	n/ac	365±4.2
18S	301±1.4	4.3±0.5	115±6.5
19S	265±3.1	5.0±0.4	19.9±0.5

^aTitrations were performed by adding aliquots of a solution of a sulfated QAO 2S, 18S or 19S to 250 nM FXIa–DEGR in 50 mM Tris–HCl buffer, pH 7.4, containing 150 mM NaCl and 0.1% PEG8000 at 37 °C and monitoring the change in fluorescence at 547 nm (λ_EX 345 nm). The maximal fluorescence change (ΔF_MAX), Hill coefficient ‘n’, and K_D were calculated using nonlinear regressional analysis (see Methods).

^bError = ± 1 SE.

^cnot applicable.