Radiochemical and biological evaluation of novel 153 Sm/ 166 Ho‐amino acid–chitosan complexes
Author(s) -
Marques F.,
Gano L.,
Batista M. K. S.,
Gomes C. A. R.,
Gomes P.,
Santos I.
Publication year - 2009
Publication title -
journal of labelled compounds and radiopharmaceuticals
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.432
H-Index - 47
eISSN - 1099-1344
pISSN - 0362-4803
DOI - 10.1002/jlcr.1571
Subject(s) - chitosan , chemistry , amino acid , biodistribution , ascorbic acid , nuclear chemistry , yield (engineering) , radiochemistry , organic chemistry , biochemistry , in vitro , food science , materials science , metallurgy
Abstract 153 Sm/ 166 Ho‐chitosan complexes have been considered promising agents for internal radiation therapy. By direct administration, complexes solution converts into a gel, at physiological pH, allowing its retention for a long time. Herein, we report on the synthesis of 153 Sm/ 166 Ho complexes with the novel amino acid–chitosan polymers, N ‐( γ ‐propanoyl‐valin)–chitosan (CHICO‐val) and N ‐( γ ‐propanoyl‐aspartic acid)–chitosan (CHICO‐asp). The main goal of this study was to obtain data on the radiochemical and biological behaviour of these complexes and information regarding their therapeutic potential when compared to 153 Sm/ 166 Ho‐chitosan. Radiolabelling yield of 153 Sm/ 166 Ho‐amino acid–chitosan complexes was dependent on polymer concentration but less dependent on pH. Radiochemical stability was shown to be higher for amino acid–chitosans than for chitosan, with 153 Sm/ 166 Ho‐CHICO‐val being stable up to 3 h, while 153 Sm/ 166 Ho‐CHICO‐asp is stable up to 24 h. In the presence of ascorbic acid radiochemical stability of 153 Sm/ 166 Ho‐CHICO‐val and 153 Sm/ 166 Ho‐CHICO was improved, decreasing for 153 Sm/ 166 Ho‐CHICO‐asp. In vivo behaviour of 153 Sm complexes was studied in mice. The radioactive amino acid–chitosans can be directly injected into blood stream without significant retention on injection site, being trapped by liver. Biodistribution studies suggest that the radioactive amino acid–chitosans, due to its water solubility and stability may be considered potential candidates to be further explored for liver targeted nuclear therapy. Copyright © 2008 John Wiley & Sons, Ltd.