Gadolinium Complexes Attached to Poly Ethoxy Ethyl Glycinamide (PEE-G) Dendrons: Magnetic Resonance Imaging Contrast Agents with Increased Relaxivity

Rinu Shrestha; Paul H Teesdale-Spittle; Andrew R Lewis; Phillip M Rendle

doi:10.1002/cplu.202000409

Gadolinium Complexes Attached to Poly Ethoxy Ethyl Glycinamide (PEE-G) Dendrons: Magnetic Resonance Imaging Contrast Agents with Increased Relaxivity

Chempluschem. 2020 Aug;85(8):1881-1892. doi: 10.1002/cplu.202000409.

Authors

Rinu Shrestha¹, Paul H Teesdale-Spittle¹, Andrew R Lewis^{1

2}, Phillip M Rendle¹

Affiliations

¹ Victoria University of Wellington, PO Box 33 436, Petone, 5046, New Zealand.
² Callaghan Innovation, PO Box 31 310, Lower Hutt, 5010, New Zealand.

PMID: 32845091
DOI: 10.1002/cplu.202000409

Abstract

A range of poly ethoxy ethyl glycinamide (PEE-G) dendron scaffolds with gadolinium (III) complexes attached were synthesized with a focus on product purity and high Gd(III) loading. The nuclear magnetic resonance relaxivity of these products was measured and compared with commercially available low-molecular-weight magnetic resonance imaging contrast agents. Over twice the relaxivity based on Gd(III) concentration, and up to 20-fold increase in relaxivity were observed based on molecular concentration. Relaxivity properties were observed to increase with both increasing molecular weight and number of Gd(III) complexes attached, however a plateau was reached for molecular weight increase. T₁ and T₂ relaxivity properties were also investigated at two different magnetic fields. Transverse relaxivity is unaffected by magnetic field strength whereas increase in longitudinal relaxivity was not as pronounced at the higher field.

Keywords: contrast agents; dendrimers; gadolinium; magnetic resonance imaging; relaxivity.

Publication types

Research Support, Non-U.S. Gov't