Probing T 1 -T 2 interactions and their imaging implications through a thermally responsive nanoprobe

The complex and specialised diagnostic process through magnetic resonance imaging (MRI) could be simplified with the implementation of dual T -T contrast agents. T - and T -weighted MR are compatible modalities, and co-acquisition of contrast enhanced images in both T and T will drastically reduce artefacts and provide double-checked results. To date, efforts in the development of dual MRI probes have provided inconsistent results. Here we present the preparation and relaxometric study of a dual T -T MRI probe based on superparamagnetic nanoparticles, paramagnetic Gd chelates and pNIPAM (poly(N-isopropylacrylamide)), in which the distance between paramagnetic and superparamagnetic species can be modulated externally via temperature variations. Such a probe alleviates traditional nanotechnology limitations (e.g. batch to batch variability) as comparisons can be established within a single probe.