Use of a Genetically Engineered Protein for the Design of a Multivalent MRI Contrast Agent
Citations Over TimeTop 15% of 2007 papers
Abstract
The majority of clinically used contrast agents (CAs) for magnetic resonance imaging have low relaxivities and thus require high concentrations for signal enhancement. Research has turned to multivalent, macromolecular CAs to increase CA efficiency. However, previously developed macromolecular CAs do not provide high relaxivities, have limited biocompatibility, and/or do not have a structure that is readily modifiable to tailor to particular applications. We report a new family of multivalent, biomacromolecular, genetically engineered protein polymer-based CAs; the protein backbone contains evenly spaced lysines that are derivatized with gadolinium (Gd(III)) chelators. The protein's length and repeating amino acid sequence are genetically specified. We reproducibly obtained conjugates with an average of 8-9 Gd(III) chelators per protein. These multivalent CAs reproducibly provide a high relaxivity of 7.3 mM (-1) s (-1) per Gd(III) and 62.6 mM (-1) s (-1) per molecule. Furthermore, they can be incorporated into biomaterial hydrogels via chemical cross-linking of the remaining free lysines, and provide a dramatic contrast enhancement. Thus, these protein polymer CAs could be a useful tool for following the evolution of tissue engineering scaffolds.
Related Papers
- → Contrast adaptation may enhance contrast discrimination(2002)48 cited
- → On Task Contrast and Visibility(1976)2 cited
- → A Note on Maximized Posttest Contrasts(1979)1 cited
- → Contrast in visual selective attention: just another feature?(2010)
- Defining and Classifying "Contrast" as a Semantic Category in Modern Chinese(2009)