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Nitronylnitroxides are promising materials for the preparation of unusual magnetic systems, particularly when coordinated with transition metal ions. In this work mono- and multilayers of the amphiphilic radical 2-tridecyl-4,4,5,5-tetramethyl-imidazolidine-1-oxyl-3-oxide radical were characterized from its spreading isotherms and by optical and ESR spectroscopy. The time stability of the films was also studied. [ABSTRACT FROM AUTHOR]

The effect of the presence of the sphingolipid ceramide (CER) on the properties of vsicles of dioleoxylphosphatidylcholine (DOPC) has been investigated by electron paramagnetic resonance (EPR) of doxyl stearic acid (DXSA) with the oxazolidinyl ring in different positions on the alkyl chain. CER acted as a condensing agent at temperature near the gel-liquid crystal phase transition temperature (Tc), whereas it acted as a fluidizer at T well above Tc. This occurred in the double-layer region from the water-lipid interface down to the double-bond system of the oleoyl residues of DOPC. Spreading isotherms of DOPC and DOPC/CER mixtures at T ∼ Tc confirmed the ESR results. [ABSTRACT FROM AUTHOR]

The surface and the aggregation properties of the nickel(II) compounds with the dibenzo- and dinaphtho-tetraazal[14]annulene (TAA) macrocycles have been investigated by their spreading isotherms and electronic spectra. The possibility to form LB films was checked for both compounds. Homogeneous, reproducible LB films were obtained with the dibenzo-TAA derivatives, whereas the high surface viscosity prevented a good multilayer overlapping with the dinaphtho-compound. [ABSTRACT FROM AUTHOR]