title: Tyramine-containing poly(4-nitrophenylacrylate) as iodinatable ligand carrier in biodistribution analysis.
abstract: OBJECTIVE
  Targeted label or drug delivery requires access to convenient carrier systems and methods for efficient ligand conjugation. The main purpose of this study is to design an iodinatable synthetic polymer, whose application in vivo in tumor-bearing mice is tested with several related carbohydrate ligands, namely ABH and Lewis blood group epitopes.
  
  
  METHODS
  Tyramine and aminopropyl derivatives of the synthetic oligosaccharides were attached to poly(4-nitrophenylacrylate). Following iodination, the biodistribution of the sugar-free and the substituted polymers was determined in tumor-bearing mice. Flow cytofluorimetric analysis assessed tumor cell binding of further ligand types to human tumor cells in vitro.
  
  
  RESULTS
  Quantitative ligand incorporation was achieved under mild conditions. Whereas the ligand-free poly[N-(2-hydroxyethyl)acrylamide] (MW 30 kDa) showed preferential accumulation in kidney, neoglycopolymers were found in substantial amounts in liver, kidney or spleen. The nature of the carbohydrate structure quantitatively influenced the distribution pattern. Tumor cell binding of blood group determinants and three further ligand types revealed non-uniform intensity in labeling and percentage of positive cells even in comparison between lines with identical histogenetic origin.
  
  
  CONCLUSIONS
  Carbohydrate-exposing poly[N-(2-hydroxyethyl)acrylamide] polymers with tyramine as an iodine acceptor distribute in mice with a profile which is quantitatively influenced by small structural variations of the ligand part. Further refinement of the ligand structure may increase the level of selectivity for organ and tumor accumulation.
authors.affiliation: Department of Biomedical Science-1, Research Institute for Biosciences, Science University of Tokyo, Noda-Shi, Chiba, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kojima
authors.forename: S
authors.initials: S
authors.lastname: André
authors.forename: E Y
authors.initials: EY
authors.lastname: Korchagina
authors.forename: N V
authors.initials: NV
authors.lastname: Bovin
authors.forename: H J
authors.initials: HJ
authors.lastname: Gabius
mesh_terms: D000180:Acrylic Resins / Q000493:pharmacokinetics*; D000818:Animals; D002240:Carbohydrate Sequence; D004337:Drug Carriers; D005434:Flow Cytometry; D006801:Humans; D007455:Iodine / Q000737:chemistry*; D051379:Mice; D008969:Molecular Sequence Data; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured; D014439:Tyramine / Q000032:analysis*
chemical_list: D000180:Acrylic Resins; D004337:Drug Carriers; C107926:poly(4-nitrophenylacrylate); D007455:Iodine; D014439:Tyramine