TY - JOUR
T1 - 64Cu core-labeled nanoparticles with high specific activity via metal-free click chemistry
AU - Zeng, Dexing
AU - Lee, Nam S.
AU - Liu, Yongjian
AU - Zhou, Dong
AU - Dence, Carmen S.
AU - Wooley, Karen L.
AU - Katzenellenbogen, John A.
AU - Welch, Michael J.
PY - 2012/6/26
Y1 - 2012/6/26
N2 - Figure Persented: A novel strategy based on metal-free "click" chemistry was developed for the copper-64 radiolabeling of the core in shell-cross-linked nanoparticles (SCK-NPs). Compared with Cu(I)-catalyzed click chemistry, this metal-free strategy provides the following advantages for Cu-64 labeling of the core of SCK-NPs: (1) elimination of copper exchange between nonradioactive Cu in the catalyst and DOTA-chelated Cu-64; (2) elimination of the internal click reactions between the azide and acetylene groups in the same NPs; and (3) increased efficiency of the click reaction because water-soluble Cu(I) does not need to reach the hydrophobic core of the NPs. When 50 mCi Cu-64 was used for the radiolabeling, the specific activity of the radiolabeled product was 975 Ci/μmol at the end of synthesis, which represents the attachment of ca. 500 Cu-64 atoms per SCK-NP, giving in essence a 500-fold amplification of specific activity of the NP over that of the Cu-64 chelate. To the best of our knowledge, this is the highest specific activity obtained for Cu-64-labeled nanoparticles.
AB - Figure Persented: A novel strategy based on metal-free "click" chemistry was developed for the copper-64 radiolabeling of the core in shell-cross-linked nanoparticles (SCK-NPs). Compared with Cu(I)-catalyzed click chemistry, this metal-free strategy provides the following advantages for Cu-64 labeling of the core of SCK-NPs: (1) elimination of copper exchange between nonradioactive Cu in the catalyst and DOTA-chelated Cu-64; (2) elimination of the internal click reactions between the azide and acetylene groups in the same NPs; and (3) increased efficiency of the click reaction because water-soluble Cu(I) does not need to reach the hydrophobic core of the NPs. When 50 mCi Cu-64 was used for the radiolabeling, the specific activity of the radiolabeled product was 975 Ci/μmol at the end of synthesis, which represents the attachment of ca. 500 Cu-64 atoms per SCK-NP, giving in essence a 500-fold amplification of specific activity of the NP over that of the Cu-64 chelate. To the best of our knowledge, this is the highest specific activity obtained for Cu-64-labeled nanoparticles.
KW - copper-64 radiolabeling
KW - high specific activity
KW - metal-free click chemistry
KW - shell-cross-linked nanoparticles
KW - specific activity amplification
UR - http://www.scopus.com/inward/record.url?scp=84862899990&partnerID=8YFLogxK
U2 - 10.1021/nn300974s
DO - 10.1021/nn300974s
M3 - Article
C2 - 22548282
AN - SCOPUS:84862899990
VL - 6
SP - 5209
EP - 5219
JO - ACS Nano
JF - ACS Nano
SN - 1936-0851
IS - 6
ER -