Table 1.

Physicochemical properties and portal vein PK parameters following intraluminal injection of salmon calcitonin or Exenatide with PIP 640 or without (control) into rat jejunum.

Peptide drug	MW (kDa)	Hydrodynamic size (Å)(calculated)	AUC(t 0–60) (ng/ml*min)		Cmax (ng/ml)
			Control	PIP 640	Control	PIP 640
Calcitonin	3.4	11	155±2.7	1680±540	3.3±0.36	55.6±6.7
Exenatide	4.2	11	237.6±38	1577±72.3	6.5±0.75	53±5.8

MW = molecular weight. The hydrodynamic radius was calculated using the relationship established between the MW and the hydrodynamic radius of a protein. PK parameters for area under the curve between 0–60 min (AUC _{t 0–60}) and maximum concentration achieved (Cmax) were calculated with the trapezoid rule using Microsoft Excel add-in program, PK-Solver [24].