Responsive molecular contrast agents for non-invasive neuroimaging

Our efforts to understand complex cellular networks would be greatly aided by next generation non-invasive measurement techniques such as Magnetic Resonance Imaging (MRI) that combine molecular specificity with whole‑organ coverage. Molecular contrast agents that not only specifically map molecular processes at high spatial resolution but also deliver temporally resolved signals are particularly suited for studying neuronal signal processing. Genetic control over these molecular agents can furthermore allow for specific targeting to neuronal subpopulations of interest. In this talk I will present recent work on responsive contrast agents for MRI based on genetically encoded metalloproteins and a reporter enzyme that interacts with metallated substrates including superparamagnetic iron oxide particles (SPIOs). I will describe the respective contrast mechanisms and design features of these molecular agents, their validation in vitro and in vivo and discuss future prospects for biological and synthetic nanostructures for non-invasive bioimaging.