TY - JOUR
T1 - 8696-8701 Utilizing electrostatic interactions to facilitate F-18 radiolabeling of poly(amido)amine (PAMAM) dendrimers
AU - Zhou, Dong
AU - Kim, Sung Hoon
AU - Carroll, Vincent M.
AU - Dence, Carmen S.
AU - Katzenellenbn, John A.
N1 - Publisher Copyright:
© The Royal Society of Chemistry 2014.
PY - 2014/11/21
Y1 - 2014/11/21
N2 - The development of methods for the facile conjugation and radiolabeling of poly(amido)amine (PAMAM) dendrimers would be of great benefit in evaluating biomedical applications of these intriguing molecularly defined polymers. Two anionic N-hydroxysuccinimide (NHS) esters (7 and 10) were developed and radio-labeled with fluorine-18 using Cu(I)-catalyzed click reactions. The radiolabeling of a primary amine-terminated PAMAM generation-6 (G6) dendrimer with [18F]7 or [18F]10 was complete in water or methanol within 5 min at room temperature. This highly efficient conjugation reaction benefits from a high, localized concentration of these NHS esters on the surface of PAMAM dendrimers, due to the electrostatic attraction between the anionic NHS esters and the positively-charged PAMAM dendrimers. The large medium effect (pH, salt, solvent) observed for these conjugation reactions is consistent with this mechanism. This novel strategy of utilizing electrostatic interactions provides a novel, facile, and efficient method for the conjugation and radiolabeling of PAMAM dendrimers that also has potential for radiolabeling other appropriate nanoparticles.
AB - The development of methods for the facile conjugation and radiolabeling of poly(amido)amine (PAMAM) dendrimers would be of great benefit in evaluating biomedical applications of these intriguing molecularly defined polymers. Two anionic N-hydroxysuccinimide (NHS) esters (7 and 10) were developed and radio-labeled with fluorine-18 using Cu(I)-catalyzed click reactions. The radiolabeling of a primary amine-terminated PAMAM generation-6 (G6) dendrimer with [18F]7 or [18F]10 was complete in water or methanol within 5 min at room temperature. This highly efficient conjugation reaction benefits from a high, localized concentration of these NHS esters on the surface of PAMAM dendrimers, due to the electrostatic attraction between the anionic NHS esters and the positively-charged PAMAM dendrimers. The large medium effect (pH, salt, solvent) observed for these conjugation reactions is consistent with this mechanism. This novel strategy of utilizing electrostatic interactions provides a novel, facile, and efficient method for the conjugation and radiolabeling of PAMAM dendrimers that also has potential for radiolabeling other appropriate nanoparticles.
UR - http://www.scopus.com/inward/record.url?scp=84930901446&partnerID=8YFLogxK
U2 - 10.1039/c4ob01616e
DO - 10.1039/c4ob01616e
M3 - Article
C2 - 25254430
AN - SCOPUS:84930901446
SN - 1477-0520
VL - 12
SP - 8696
EP - 8701
JO - Organic and Biomolecular Chemistry
JF - Organic and Biomolecular Chemistry
IS - 43
ER -