title: New complexing agents for labeling of proteins with metals.
abstract: The applicability of bifunctional chelating agents in the labeling of proteins was analysed by using Eu-labeled antibodies as a model system. The requirements set for chelate stability are defined mainly by the system and metals used. The chelates used for in vitro applications cannot necessarily be utilized in in vivo experiments in which the competing chelating agents and metals set great demands on the inertness of the chelates against ligand changes. An isothiocyanatobenzyl derivative of diethyelenetriaminetetraacetic acid showed excellent stability in the conditions under investigation. The coupling reaction is mild and allows simple addition of metals within or after the coupling of the chelator to the protein, which makes it a good choice for the labeling of antibodies with metals like Gd3+.
authors.affiliation: Wallac Chemical Laboratories, Turku, Finland.
authors.forename: I A
authors.initials: IA
authors.lastname: Hemmilä
authors.forename: H J
authors.initials: HJ
authors.lastname: Mikola
mesh_terms: D000906:Antibodies; D002614:Chelating Agents; D004355:Drug Stability; D005063:Europium; D006801:Humans; D007553:Isotope Labeling; D008670:Metals; D011506:Proteins
chemical_list: D000906:Antibodies; D002614:Chelating Agents; D008670:Metals; D011506:Proteins; D005063:Europium