Jump to main content
Jump to site search

Issue 4, 2014
Previous Article Next Article

MRI ParaCEST agents that improve amide based pH measurements by limiting inner sphere water T2 exchange

Author affiliations

Abstract

A series of Dy3+ and Tm3+ tetra-substituted DOTAM paraCEST agents incorporating para-substituted anilines has been synthesized and their paraCEST and relaxation properties evaluated. The response of selected agents (aniline and p-methoxyaniline) to changes in pH near the physiological range has also been studied. A crystal structure of Tm3+-p-OMe agent indicates a TSAP geometry with the absence of an inner sphere water molecule (denoted as TSAP'), which is thought to be due to the bulky nature of the amide nitrogen substituent. Two distinct amide signals are observed in the CEST spectrum for this compound, one for each of the isomers that exist in solution: SAP and TSAP with the larger chemical shift centred at −83 ppm compared to bulk water. Due to the non-optimal inner sphere water exchange, these agents produce minimal shortening of T1 and T2 relaxation time constants and therefore decrease relaxation induced signal losses during imaging.

Graphical abstract: MRI ParaCEST agents that improve amide based pH measurements by limiting inner sphere water T2 exchange

Back to tab navigation

Supplementary files

Article information


Submitted
11 Jul 2013
Accepted
28 Oct 2013
First published
29 Oct 2013

RSC Adv., 2014,4, 1666-1674
Article type
Paper

MRI ParaCEST agents that improve amide based pH measurements by limiting inner sphere water T2 exchange

M. Milne, M. Lewis, N. McVicar, M. Suchy, R. Bartha and R. H. E. Hudson, RSC Adv., 2014, 4, 1666
DOI: 10.1039/C3RA43537G

Social activity

Search articles by author

Spotlight

Advertisements