C12425: MRI-based Non-Invasive Metal Ion Detection System
Novelty: Novel method combining chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) with 19F fluorinated chelators to detect free metal ions with high sensitivity and specificity.
Value Proposition: Although metal ions are involved in a myriad of biological processes, non-invasive detection of free metal ions in deep tissue remains a formidable challenge. This invention presents an approach for specific sensing of the presence of metal ions in which the amplification strategy of CEST is combined with the broad range of chemical shifts found in 19F NMR spectroscopy to obtain magnetic resonance images of the metal ions. Additional advantages include:
• Produces images without background signal
• Non-invasive
• Highly sensitive to the details of local environment
• 19F has a 20 times larger range compared to water-based CEST imaging
• High specificity allows detection of ions in the presence of competing ions
Technical Details: Johns Hopkins researchers have developed a new imaging technique called ion CEST (iCEST) to detect free metal ions in vivo. The system combines the sensitivity and large range of chemical shifts observed in 19F NMR spectra with the MRI signal amplification technique. In order to detect a specific metal ion and determine the concentration, a 19F fluorinated chelator binds the specific metal ion causing a chemical shift change, which is detected by radiofrequency labeling at chelator-metal ion complex frequency, paired with the detection of label transfer to the free 19F chelator frequency. By analyzing the exchange of free 19F chelate and the 19F chelator-metal ion complex, the ion concentration (as low as nM range) can be indirectly determined.
Looking for Partners: To develop & commercialize the technology as an in vivo metal ion sensor for biological research and clinical diagnosis.
Patent Status: Pending US Application US-2016-0091443
Data Availability: Under CDA / NDA
Publications/Associated Cases: J Am Chem Soc. 2013 Aug 21;135(33):12164-7
