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Switchable MRI contrast agents based on morphological changes of pH-responsive polymers.

Abstract：

:Magnetic resonance imaging (MRI) contrast agents are effective tools in both medical diagnosis and life science research. Various smart contrast agents have been developed for the visualization of biological phenomena. These contrast agents have molecular switches that increase or reduce MRI signal intensity in response to the target biological reaction. Therefore, novel approaches to the design of molecular switches for versatile in vivo studies using MRI are eagerly anticipated. Here, we report one such approach for the development of molecular switches based on morphological changes of pH-responsive polymers. We designed and synthesized three types of contrast agents based on a linear homopolymer or spherical copolymers with two different cross-linking degrees. The relaxivity measurements showed that these agents have molecular switches that respond to pH changes, and fluorescence studies indicated that these switches are based on the alteration of the molecular tumbling caused by pH-responsive morphological changes. As a result, the spherical polymers possess promising characteristics for the development of switchable MRI contrast agents.

journal_name

Bioorg Med Chem

journal_title

Bioorganic & medicinal chemistry

authors

Okada S,Mizukami S,Kikuchi K

doi

10.1016/j.bmc.2011.12.005

subject

Has Abstract

pub_date

2012-01-15 00:00:00

pages

769-74

issue

2

eissn

0968-0896

issn

1464-3391

pii

S0968-0896(11)01011-X

journal_volume

20

pub_type

杂志文章

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