title: Characterization of (111)In(3+) complexes of DTPA amide derivatives: biodistribution and clearance studied by gamma imaging.
abstract: A large series of structurally related diethylenetriaminepentaacetic acid amide derivatives with different structures and lipophilic properties were synthesized and radiolabeled with (111)In(3+). Two of the more hydrophobic compounds studied ([(111)In]L(9) and [(111)In]L(10)) showed high affinity for human serum albumin (HSA). The biodistribution and clearance properties shown by all complexes upon injection in Wistar rats were followed by gamma imaging. The blood retention time of the chelates correlates better with their binding to HSA than with their hydrophilic/lipophilic ratio. Hydrophilic and negatively charged complexes undergo renal retention, while the majority of the lipophilic complexes are retained in the blood for a longer period of time and are cleared through the liver.
authors.affiliation: Serviço de Biofísica e Biomatemática, Fac. Medicina, Universidade de Coimbra, Coimbra, Portugal.
authors.forename: M I
authors.initials: MI
authors.lastname: Prata
authors.forename: A C
authors.initials: AC
authors.lastname: Santos
authors.forename: S W
authors.initials: SW
authors.lastname: Bligh
authors.forename: A H
authors.initials: AH
authors.lastname: Chowdhury
authors.forename: C F
authors.initials: CF
authors.lastname: Geraldes
authors.forename: J J
authors.initials: JJ
authors.lastname: de Lima
mesh_terms: D000818:Animals; D002614:Chelating Agents / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics; D015902:Gamma Cameras; D007205:Indium Radioisotopes / Q000737:chemistry; D007668:Kidney / Q000000981:diagnostic imaging / Q000378:metabolism; D008099:Liver / Q000000981:diagnostic imaging / Q000378:metabolism; D008657:Metabolic Clearance Rate; D000442:Octanols / Q000737:chemistry; D004369:Pentetic Acid / Q000031:analogs & derivatives / Q000737:chemistry* / Q000378:metabolism / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D012709:Serum Albumin / Q000378:metabolism; D014018:Tissue Distribution
chemical_list: D002614:Chelating Agents; D007205:Indium Radioisotopes; C417907:N,N-bis(2-(bis(2-ethylhexylcarbamoylethyl)amino)ethyl)glycine; C417908:N,N-bis(2-(bis(n-heptylcarbamoyl)amino)ethyl)glycine; D000442:Octanols; D019275:Radiopharmaceuticals; D012709:Serum Albumin; D004369:Pentetic Acid