The binding of the sdAb-aGST-MESNA to GST assayed with SPR and ELISA. (A) SPR analysis of sdAb-aGST-MESNA binding to GST. Insert: steady state responses were plotted against the concentration. The line represents a fit to a one-site binding model using a K
of 116 nM. (B) ELISA measurement of binding of sdAb-aGST to GST (square) fitted with a one-site binding model using a KD of 77 nM and BSA (circle).