Chelator free gallium-68 radiolabelling of silica coated iron oxide nanorods via surface interactions

Burke, Benjamin P.; Baghdadi, Neazar; Kownacka, Alicja E.; Nigam, Shubhanchi; Clemente, Gonçalo S.; Al-Yassiry, Mustafa M.; Domarkas, Juozas; Lorch, Mark; Pickles, Martin; Gibbs, Peter; Cawthorne, Christopher; Archibald, Stephen J.

Abstract

The commercial availability of combined magnetic resonance imaging (MRI)/positron emission tomography (PET) scanners for clinical use has increased demand for easily prepared agents which offer signal or contrast in both modalities. Herein we describe a new class of silica coated iron–oxide nanorods (NRs) coated with polyethylene glycol (PEG) and/or a tetraazamacrocyclic chelator (DO3A). Studies of the coated NRs validate their composition and confirm their properties as in vivo T₂ MRI contrast agents. Radiolabelling studies with the positron emitting radioisotope gallium-68 (t1/2 = 68 min) demonstrate that, in the presence of the silica coating, the macrocyclic chelator was not required for preparation of highly stable radiometal-NR constructs. In vivo PET-CT and MR imaging studies show the expected high liver uptake of gallium-68 radiolabelled nanorods with no significant release of gallium-68 metal ions, validating our innovation to provide a novel simple method for labelling of iron oxide NRs with a radiometal in the absence of a chelating unit that can be used for high sensitivity liver imaging.

Citation

Burke, B. P., Baghdadi, N., Kownacka, A. E., Nigam, S., Clemente, G. S., Al-Yassiry, M. M., Domarkas, J., Lorch, M., Pickles, M., Gibbs, P., Cawthorne, C., & Archibald, S. J. (2015). Chelator free gallium-68 radiolabelling of silica coated iron oxide nanorods via surface interactions. Nanoscale, 7(36), 14889-14896. https://doi.org/10.1039/c5nr02753e

• Acceptance Date: Aug 6, 2015
• Online Publication Date: Aug 13, 2015
• Publication Date: Aug 13, 2015
• Deposit Date: Dec 16, 2015
• Publicly Available Date: Nov 23, 2017
• Journal: Nanoscale
• Print ISSN: 2040-3364
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Issue: 36
• Pages: 14889-14896
• DOI: https://doi.org/10.1039/c5nr02753e
• Keywords: Nanorods, Polyethylene glycol , Tetraazamacrocyclic chelator , Gallium-68 , Iron oxide
• Public URL: https://hull-repository.worktribe.com/output/382862
• Publisher URL: http://pubs.rsc.org/en/Content/ArticleLanding/2015/NR/C5NR02753E#!divAbstract
• Additional Information: Copy of article first published in: Nanoscale, 2015, v.7, issue 36.
• Contract Date: Nov 23, 2017