Maximizing T2-exchange in Dy(3+)DOTA-(amide)X chelates: fine-tuning the water molecule exchange rate for enhanced T2 contrast in MRI.

ABSTRACT:

Purpose

The water molecule exchange rates in a series of DyDOTA-(amide)X chelates were fine-tuned to maximize the effects of T2-exchange line broadening and improve T2 contrast.

Methods

Four DyDOTA-(amide)X chelates having a variable number of glycinate side-arms were prepared and characterized as T2-exchange agents. The nonexchanging DyTETA chelate was also used to measure the bulk water T2 reduction due solely to T2*. The total transverse relaxivity (r2tot) at 22, 37, and 52°C for each chelate was measured in vitro at 9.4 Tesla (400 MHz) by fitting plots of total T2 (-1) versus concentration. The water molecule exchange rates for each complex were measured by fitting (17)O line-width versus temperature data taken at 9.4 Tesla (54.3 MHz).

Results

The measured transve

SUBMITTER: Soesbe TC 

PROVIDER: S-EPMC4219925 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature