Specific and stable labeling of antibodies with technetium-99m with a diamide dithiolate chelating agent.
Technetium-99m labeling of antibodies has been suboptimal because of low affinity adventitious binding, nonspecific labeling, and loss of immunoreactivity. The diamide dithiolate ligand system (N2S2) forms highly stable, well-defined tetradentate complexes with Tc(V). Antibodies and their fragments have been labeled by conjugation of preformed 99mTc-4,5-bis(thioacetamido)pentanoate active ester to protein amine groups to give a chemically known 99mTc-N2S2 complex covalently linked to antibody. Evaluations of the 99mTc-N2S2-bound antibodies and their fragments have shown high stability and retained immunoreactivity.
Fritzberg
A R
AR
NeoRx Corporation, Seattle, WA 98119.
Abrams
P G
PG
Beaumier
P L
PL
Kasina
S
S
Morgan
A C
AC
Rao
T N
TN
Reno
J M
JM
Sanderson
J A
JA
Srinivasan
A
A
Wilbur
D S
DS
D000818:Animals; D000906:Antibodies; D000912:Antibodies, Neoplasm; D001391:Azo Compounds; D002614:Chelating Agents; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D003958:Diamide; D007140:Immunoglobulin Fab Fragments; D008024:Ligands; D008546:Melanoma, Experimental / Q000000981:diagnostic imaging; D051379:Mice; D011877:Radionuclide Imaging / Q000379:methods*; D013667:Technetium
D000906:Antibodies; D000912:Antibodies, Neoplasm; D001391:Azo Compounds; D002614:Chelating Agents; D007140:Immunoglobulin Fab Fragments; D008024:Ligands; D003958:Diamide; D013667:Technetium