Synthesis and evaluation of a new bifunctional chelating agent for 99mTc labeling proteins: p-carboxyethylphenylglyoxal-di(N-methylthiosemicarbazone).
A new bifunctional chelating agent, p-carboxyethylphenylglyoxal-di(N-methylthiosemicarbazone) (CE-DTS), containing a di(N-methylthiosemicarbazone) as the technetium coordinating site and an aralkyl carboxylate site for the protein conjugation was synthesized. Coupling to human serum albumin (HSA), selected as a model protein was carried out by the phosphorylazide method using diphenylphosphoryl azide (DPPA). The conjugation level of CE-DTS to HSA played a critical role in its biological evaluation. A 99mTc-CE-DTS-HSA with high in vivo stability was obtained when CE-DTS was coupled to HSA at 1:1 molar ratio. This compound showed similar in vivo stability to 131I labeled HSA in mice and rabbits.
Y
Y
Arano
A
A
Yokoyama
Y
Y
Magata
H
H
Saji
K
K
Horiuchi
K
K
Torizuka
D000818:Animals; D002614:Chelating Agents / Q000138:chemical synthesis*; D003432:Cross-Linking Reagents / Q000138:chemical synthesis*; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate; D051379:Mice; D011506:Proteins / Q000378:metabolism; D011817:Rabbits; D012709:Serum Albumin / Q000378:metabolism; D013667:Technetium / Q000378:metabolism; D013882:Thiosemicarbazones / Q000138:chemical synthesis*; D014018:Tissue Distribution
D002614:Chelating Agents; D003432:Cross-Linking Reagents; D011506:Proteins; D012709:Serum Albumin; D013882:Thiosemicarbazones; D013667:Technetium; C049200:4-carboxyethylphenylglyoxal-bis(N-methylthiosemicarbazone)