Effect of Magnetic Coupling on Water Proton Relaxivity in a Series of Transition Metal Gd^III Complexes.

ABSTRACT: A fundamental challenge in the design of bioresponsive (or bioactivated) Gd^III-based magnetic resonance (MR) imaging probes is the considerable background signal present in the "preactivated" state that arises from outer-sphere relaxation processes. When sufficient concentrations of a bioresponsive agent are present (i.e., a detectable signal in the image), the inner- and outer-sphere contributions to r₁ may be misinterpreted to conclude that the agent has been activated, when it has not. Of the several parameters that determine the observed MR signal of an agent, only the electron relaxation time ( T_1e) impacts both the inner- and outer-sphere relaxation. Therefore, strategies to minimize this background signal must be developed to create a near zero-backg

SUBMITTER: Lilley LM 

PROVIDER: S-EPMC6016852 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature