Table of Contents
ISRN Molecular Imaging
Volume 2013, Article ID 386976, 8 pages
http://dx.doi.org/10.1155/2013/386976
Research Article

Ga-68- and Cu-64-Labeled NOTA-Albumin Conjugates for PET Sentinel Lymph Node Imaging

1ROTOP Pharmaka AG, Bautzner Landstraße 400, 01328 Dresden, Germany
2Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden, Germany
3Department of Nuclear Medicine, University Hospital, “Carl Gustav Carus” Fetscherstraße 74, 01307 Dresden, Germany

Received 17 December 2012; Accepted 3 January 2013

Academic Editors: N. Gillings, P. Lass, and N. Motomura

Copyright © 2013 Eik Schiller et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Our objective was to develop and evaluate Ga-68- and Cu-64-labeled albumin conjugates for PET imaging of sentinel lymph nodes. Four different albumin conjugates were prepared starting from NOTA-HSA. The lymph node uptake of Ga-68- and Cu-64-labeled albumin conjugates was investigated after subcutaneous injection into the foot pad of Wistar rats. A pig model was utilized for further biological evaluation of the lymph node uptake. For all the four conjugates, radiolabeling with Ga-68 and Cu-64 resulted in >95% radiochemical yield. Denatured and mannosylated Ga-68 NOTA-HSA revealed the highest popliteal lymph node uptake in rats ( % ID and % ID 10 min and 60 min p.i., resp.). The popliteal lymph node reached its maximum activity after approximately 120 min and remained constant for denatured and mannosylated Cu-64 NOTA-HSA at least up to 240 min p.i. In a pig model, 2% of the injected dose of this compound was found in the sentinel lymph node 60 min after subcutaneous injection. In conclusion, PET imaging of sentinel lymph nodes with Ga-68- and Cu-64-labeled denatured NOTA-Man-HSA could be successfully demonstrated and deserves further investigations.