Nuclear Imaging Evaluation of Galactosylation of Chitosan.
- Author:
Hwan Jeong JEONG
1
;
Eun Mi KIM
;
In Kyu PARK
;
Chong Su CHO
;
Chang Guhn KIM
;
Hee Seung BOM
Author Information
1. Department of Nuclear Medicine, Wonkwang University School of Medicine, Iksan, Korea. leokim@wonkwang.ac.kr
- Publication Type:Original Article
- Keywords:
99mTc;
hepatocyte-targeted;
nuclear imaging;
galactosylated chitosan
- MeSH:
Chitosan*;
Food Additives;
Galactose;
Gamma Cameras;
Hepatocytes;
Liver;
Magnetic Resonance Spectroscopy;
Methylation;
Rabbits;
Radionuclide Imaging;
Transplants;
Veins
- From:Korean Journal of Nuclear Medicine
2004;38(3):253-258
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: Chitosan has been studied as a non-viral gene delivery vector, drug delivery carrier, metal chelater, food additive, and radiopharmaceutical, among other things. Recently, galactose-graft chitosan was studied as a non-viral gene and drug delivery vector to target hepatocytes. The aim of this study was to investigate the usefulness of nuclear imaging for in vivo evaluation of targeting the hepatocyte by galactose grafting. METHODS AND MATERIALS: Galactosyl methylated chitosan (GMC) was produced by methylation to lactobionic acid coupled chitosan. Cytotoxicity of 99mTc-GMC was determined by MTT assay. Rabbits were injected via their auricular vein with 99mTc-GMC and 99mTc-methylated chitosan (MC), the latter of which does not contain a galactose group, and images were acquired with a gamma camera equipped with a parallel hole collimator. The composition of the galactose group in galactosylated chitosan (GC), as well as the tri-, di-, or mono-methylation of GMC, was confirmed by NMR spectroscopy. RESULTS: The results of MTT assay indicated that 99mTc-GMC was non-toxic. 99mTc-GMC specifically accumulated in the liver within 10 minutes of injection and maintained high hepatic uptake. In contrast, 99mTc-MC showed faint liver uptake. 99mTc-GMC scintigraphy of rabbits showed that the galactose ligand principally targeted the liver while the chitosan functionalities led to excretion through the urinary system. CONCLUSION: Bioconjugation with a specific ligand endows some degree of targetability to an administered molecule or drug, as in the case of galactose for hepatocyte in vivo, and evaluating said targetabililty is a clear example of the great benefit proffered by nuclear imaging.
