Multi-Modality PET-MR Perfluorocarbon Nanoparticle Contrast Agent for Ligand-Targeted Quantitative Imaging

Introduction. The combination of positron emission tomography and magnetic resonance imaging offers a major breakthrough in detecting, characterizing and monitoring disease. This work introduces a novel contrast agent, detected by both modalities, which employs a self-inserting chelator with linker peptide derived from melittin (a host defense peptide in honeybee venom). Based on a lipid-encapsulated perfluorocarbon (PFC) nanoparticle (NP) [1], which has previously been modified for SPECT imaging [2,3], the proposed Cu-labeled molecular imaging agent can be sensitively detected and localized with whole-body PET, directing the focal acquisition of high resolution, high specificity MR imaging. The liquid perfluorocarbon core can be imaged directly with F MRI, independent of gadolinium or iron for paramagnetic effects. The objective of this work is to synthesize the peptide linker to chelate Cu, label PFC NP and demonstrate the first quantitative imaging of the multi-modality PET-MR agent in vitro.