Three iron(III) complexes with ligands derived from N-ethyl-N-(2-aminoethyl) salicylaldiminate (H, 1; 5-Br, 2; 3-OMe, 3 substituents at the phenyl group) were prepared and the X-ray crystal structures of 1 and 2 are reported. NMR studies of solutions of these complexes in DMSO allowed for investigation of their magnetic behaviour and paramagnetic relaxation contribution. The relaxivities measured ranged from 0.35 to 0.80 mM(-1) s(-1) for proton Larmor frequencies from 0.01 to 300 MHz, in agreement with those known for other iron(III) based contrast agents. Biological studies on colonic epithelial T-84 cell monolayers showed that the compounds exert toxic effects only at concentrations higher than 100 mu M while coincidently reducing colonic epithelial secretory function. These two features make these complexes good candidates for further development in order to be used as MRI contrast agents. (C) 2015 Elsevier B.V. All rights reserved.

Molecular mobility is a fundamental parameter which reflects the dynamic properties of food components and contributes to food degradation reactions comprehension. Fresh-cut fruits have become an important food market segment. However, processing of fruits promotes faster its physiological deterioration, biochemical changes and microbial degradation. The purpose of this work was to use NMR methodology as a tool to evaluate fresh-cut fruit quality, during storage at refrigerated conditions. The fresh-cut melon transverse relaxation time (T-2) was measured for a period of 7 days of storage at 5 degrees C. The relationship between the obtained values, microstructure and quality parameters was investigated. In general, results show the existence of one class of water fluidity in the system, the one present in cells after processing. T-2, a measure of this fluidity, is affected by the processing and storage time. Also, it is possible to find a close relationships between T-2 and quality parameters of total colour difference (TCD), firmness and a(w). As T-2 increases TCD also increases, while firmness and aw decrease. These results highlight the usefulness of NMR methodology application in food science. (C) 2015 Elsevier Ltd. All rights reserved.