Subnanosize thermometric NMR sensors based on paramagnetic lanthanide(III) complexes with EDTA for temperature control in aqueous media and in magnetoresonance tomography

摘要

Complexes of ethylenediaminetetraacetic acid (EDTA) with Gd~(III)are successfully used as in vivo contrast relaxation agents for medical magnetoresonance tomography (MMRT). The temperature dependence of the molecular paramagnetic susceptibility, which is described by the linear approximation on the inverse temperature (LAIT) in the temperature range from 260 to 400 K, has previously been described experimentally for some complexes of lanthanides, except for Gd~(III). In the present work, we propose to use the LAIT ependence of the paramagnetic lanthanide-induced shifts (LIS) in the NMR spectra on nuclei of synthetic organic complexones of the EDTA type in kinetically stable compounds with paramagnetic lanthanide(III) cations to determine the temperature of aqueous solutions of samples placed directly in the NMR spectrometer.