Table 1. Biophysical properties of anti-TcdB V_HHs.

VHH	Panning source	Ve (mL)	SEC (%)a	Tm (°C)b	ka (M-1 s-1)	kd (s-1)	KD (nM)	Rmax (RU)c	Epitope bin
B26	solution	12.97	99.8	68.3±0.3	5.25×106	3.45×10−2	6.3	149	4
B35	solution	14.07	99.8	76.2±0.4	1.16×106	1.05×10−3	0.9	50	1
B39	solution	16.05	99.8	87.2±0.2	3.44×107	2.56×10−3	0.07	43	1
B45	solution	14.84	99.4	79.5±0.4	3.52×106	3.84×10−4	0.1	55	1
B46	solid phase	13.18	99.3	61.0±1.4	1.53×105	9.43×10−3	62	51	n.d.
B48	both	13.07	99.7	82.5±0.3	4.11×106	5.71×10−3	1.4	73	3
B52	both	12.77	99.9	65.3±0.7	1.29×107	1.01×10−2	0.8	63	3
B53	solid phase	12.97	99.6	77.1±0.0	4.38×106	7.98×10−3	1.8	72	3
B54	solution	12.85	95.3	81.7±0.3	3.86×107	1.47×10−2	0.4	65	2
B55	solid phase	13.35	99.8	66.6±1.1	3.34×105	4.93×10−2	147	142	n.d.
B56	solid phase	14.00	86.7	57.6±0.3	5.46×104	3.15×10−2	576	18	n.d.
B65	solid phase	13.26	96.3	84.4±0.2	1.32×104	2.33×10−3	176	17	n.d.
B69	solid phase	13.11	82.1	80.9±0.5	1.17×107	1.50×10−1	12.8	102	5
B71	solid phase	12.88	85.9	63.3±0.3	7.76×106	9.18×10−2	11.8	61	6
B73	both	13.41	99.7	80.2±0.0	1.27×107	9.19×10−3	0.7	63	3
B74	both	13.62	99.6	75.0±0.2	1.23×107	3.58×10−3	0.3	66	3
B76	solid phase	12.48	99.4	84.2±1.1	1.38×106	2.17×10−1	157	74	n.d.
B79	solid phase	13.48	99.1	66.9±0.1	5.59×106	9.72×10−3	1.7	75	3
B85	solution	12.94	99.4	69.7±0.1	1.93×107	1.14×10−2	0.6	73	2
B86	solution	13.03	99.6	72.9±0.1	8.25×106	3.98×10−3	0.5	71	3
B92	solid phase	12.85	98.9	78.0±0.1	1.51×106	8.28×10−1	548	72	n.d.
B94	solution	12.58	96.7	69.7±0.4	6.19×105	8.77×10−3	14.2	385	4
B95	solid phase	13.97	95.1	80.8±0.6	1.12×107	7.05×10−3	0.6	72	3
B96	solution	13.17	99.7	70.5±0.2	1.37×106	7.33×10−2	53.6	104	n.d.
B99	solution	13.05	98.7	69.8±2.2	6.33×107	1.04×10−1	1.6	76	2
B131	solution	13.01	100	69.3±2.3	5.47×107	1.40×10−1	2.6	73	7
B149	solution	13.45	97.4	83.9±0.0	4.12×104	2.20×10−2	534	133	n.d.
B158	solution	13.44	99.4	73.4±0.8	3.44×104	1.74×10−3	50.5	67	3
B167	solution	13.14	99.6	72.1±0.4	1.53×107	1.10×10−3	0.07	76	2

^a% monomer determined by area under the curve

^b(mean ± SD)

^cObserved R_max was obtained from a TcdB surface with a theoretical R_max of 200 RUs; n.d., not determined.