Figure 3. Plasma protein binding of the receptor decoys in vivo.

Rats were i.v. injected with ¹²⁵I-L56A, ¹²⁵I-sTEM8, ¹²⁵I-sCMG2 at a dose of 67.5 g/kg via the tail vein (at volume 250 µl). The serum samples collected at 5 min, 30 min, and 4 h after dosing were analyzed by size exclusion HPLC (TSK G3000 SWXL gel column)-flow scintillation analyzer (Radiomatic Model 600TRSeries, PerkinElmer, USA). For comparison, proteins labeled with ¹²⁵I were loaded directly on columns as standards. When compared with the peak of the standard, a faster peak implied plasma protein binding, whereas a delayed peak may represent degraded protein.