초록 |
MRI is a high-resolution and clinically important imaging modality, which offers anatomical information, enabling diagnosis and prognosis of disease. A considerable effort has been investigated for the development of responsive MRI contrast agents capable of specifically indicating their local microenvironment. In the presence of biological target, a switch in MRI contrast is triggered by the change of the relaxation efficiency which is derived from the variation of rotational dynamics or exchange rate of coordinated water, etc. Here, I’ll present a new design principle for the modulation of the relaxation efficiency. This magnetic resonance tuning occurs between a paramagnetic element and a superparamagnetic element, where the MRI signal is tuned On or Off depending on their separation distance. Various biological targets are successfully detected in in vitro and in vivo systems. It can serve as a novel sensing principle for a wide range of biological targets. |