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Synthesis, Characterization, and in vitro Testing of a Bacteria-Targeted MR Contrast Agent.

ABSTRACT: A bacteria-targeted MR contrast agent, Zn-1, consisting of two Zn-dipicolylamine (Zn-dpa) groups conjugated to a GdIII chelate has been synthesized and characterized. In vitro studies with S. aureus and E. coli show that Zn-1 exhibits a significant improvement in bacteria labeling efficiency vs. control. Studies with a structural analogue, Zn-2, indicate that removal of one Zn-dpa moiety dramatically reduces the agent's affinity for bacteria. The ability of Zn-1 to significantly reduce the T1 of labeled vs. unlabeled bacteria, resulting in enhanced MR image contrast, demonstrates its potential for visualizing bacterial infections in vivo.

SUBMITTER: Matosziuk LM

PROVIDER: S-EPMC3634600 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Synthesis, Characterization, and in vitro Testing of a Bacteria-Targeted MR Contrast Agent.

Matosziuk Lauren M LM Harney Allison S AS Macrenaris Keith W KW Meade Thomas J TJ

European journal of inorganic chemistry 20120401 12

A bacteria-targeted MR contrast agent, Zn-1, consisting of two Zn-dipicolylamine (Zn-dpa) groups conjugated to a GdIII chelate has been synthesized and characterized. In vitro studies with S. aureus and E. coli show that Zn-1 exhibits a significant improvement in bacteria labeling efficiency vs. control. Studies with a structural analogue, Zn-2, indicate that removal of one Zn-dpa moiety dramatically reduces the agent's affinity for bacteria. The abi ...[more]

PMID: 23626484

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