Table 1.

Main characteristics of different engineered antibody fragments.

	Molecular Weight (kDa)	Avidity	Clearance Route	Serum Half-Life	Optimal Time for Imaging	Ref.
IgG	150	Bivalent	Liver	110 h	4–7 d	[41,47]
F(ab)’2	110	Bivalent	Liver/Kidney	9 h	72–120 h	[41]
Minibody	80	Bivalent	Liver	5–12 h	24–48 h	[47]
Diabody	50	Bivalent	Kidney	2–5 h	12–24 h	[47]
Fab	55	Monovalent	Kidney	28 min	2–5 h	[41]
scFv	25	Monovalent	Kidney	10 min	1–3 h	[41]
Nb	15	Monovalent	Kidney	1–1.5 h	1–1.5 h	[41]
Affibody	6–7	Not applicable	Kidney	4–14 min	1–2 h	[41,47,48,49]