MRI Reporter Gels to Detect Enzymes and Cells in Vivo

¹Harrington Department of Bioengineering, Arizona State University, Tempe, Az, USA

Synthetic hydrogels are used to guide tissue regeneration and serve as a scaffold for drug delivery. In this work, MRI reporter gels were created containing functionalized, superparamagnetic cationic ferritin nanoparticles. These nanoparticles bound electrostatically to glycosaminoglycans in the gel, and were aggregated compared to uncharged nanoparticles. The aggregation of the bound nanoparticles was then controlled through gel digestion with two enzymes, modulating gel T2. A zymogen cascade was used to make the reporter gels degrade in the presence of picomolar target molecules. MRI reporter gels may thus be useful for detecting enzymes and cells after implantation in vivo.