title: Radiolabeling of folic acid-modified chitosan with (99m)Tc as potential agents for folate-receptor-mediated targeting.
abstract: The feasibility of chitosan (CS) as a backbone for the design of (99m)Tc-labeled targeting agent was evaluated in this study. Chitosan-folate conjugate (CSFA) and chitosan-folate dithiocarbamate (CSFADTC) were synthesized, characterized and radiolabeled with (99m)Tc as model compounds for folate-receptor (FR) targeting. (99m)Tc-complexes were prepared with high radiochemical purity and high stability. The hydrophilicities of these (99m)Tc-complexes were determined by partition coefficient experiments. The results of biodistribution in normal mice showed that the folic-acid modified agents ((99m)Tc-CSFA and (99m)TcN-CSFADTC) had obviously higher uptake in FR-positive kidney and much lower liver and spleen uptakes than that of non-folic-acid modified (99m)Tc-agent, and the kidney uptakes of FA-modified agents could be blocked significantly by the corresponding cold ligand. Furthermore in vitro and in vivo specific studies will be done in cell line and tumor bearing mice to confirm the usefulness of this chitosan backbone for FR targeting agent design.
authors.affiliation: Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, 19 Xinjiekou Outer St., Beijing 100875, China.
authors.forename: Wenyan
authors.initials: W
authors.lastname: Guo
authors.forename: Huihui
authors.initials: H
authors.lastname: Jing
authors.forename: Wenjiang
authors.initials: W
authors.lastname: Yang
authors.forename: Zhide
authors.initials: Z
authors.lastname: Guo
authors.forename: Shi
authors.initials: S
authors.lastname: Feng
authors.forename: Xianzhong
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000818:Animals; D048271:Chitosan / Q000737:chemistry* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid; D005492:Folic Acid / Q000737:chemistry*; D058972:Folic Acid Transporters / Q000187:drug effects*; D051379:Mice; D008819:Mice, Nude; D015609:Organotechnetium Compounds / Q000737:chemistry*; D011874:Radiometry; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D014018:Tissue Distribution
chemical_list: D058972:Folic Acid Transporters; D015609:Organotechnetium Compounds; D048271:Chitosan; D005492:Folic Acid