Table 1.

Comparison of kinetic and equilibrium binding constants for human IgG binding to protein A.

	ka (M-1s-1)	kd (s-1)	Ka (M-1)	Kd (M)
Time-resolved data:
171 nM equilibrium dose	1.1 ± 0.6 × 104	2.1 ± 1.0 × 10-5	5.2 ± 2.7 × 108	1.9 ± 1.0 × 10-9
51 nM equilibrium dose	1.6 ± 0.3 × 104	2.2 ± 0.1 × 10-4	7.4 ± 1.7 × 107	1.4 ± 0.3 × 10-8
171 nM 4 minute dose	1.2 ± 0.4 × 104	2.1 ± 0.2 × 10-4	5.5 ± 1.5 × 107	1.9 ± 0.5 × 10-8
Steady-state data:
171 nM equilibrium dose	-	-	3.0 ± 0.5 × 107	3.3 ± 0.6 × 10-8
Published valuesa	-	-	1.8-9.4 × 107	-
Published value, Protein A/IgG, surfaceb	8.02 × 103	2.77 × 10-4	2.9 × 107	-

^aReferences 36-⁴⁰.

^bReference 42, unknown IgG species.