Síntese e caracterização de nanocomplexos de íons lantanídeos (III) com β-Dicetona e ligantes heterobiaris: perspectiva de aplicação como marcadores biológicos.

Abstract

Lanthanides accompany lighting systems since their beginnings, and there are no equivalent substitutes for the generation of light in current systems, so that such elements are already present in the future of photoluminescent devices. In this perspective, the present work consisted of the synthesis and characterization of new nanocomplexes of the formula Ln(β-diketone)3Heterobials. Ln are the lanthanides Nd3+ and Er3 + , β-diketone corresponds to 4,4,4-trifluoro-1-phenill-1 , 3-butadione (Btfa) and the second Heterobials binders: 2,2 bipyridine and 1,10 phenanthroline, with a view to using them as biological markers. The nanocomplexes were synthesized from their respective chlorides through the direct reaction between the salt and the binders and then were characterized by means of elementary analysis, absorption spectroscopy in the infrared and UV-visible region, RAMAN spectroscopy, X Ray Diffraction (XRD), scanning electron microscopy (SEM), determination of the melting/decomposition intervals, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and differential thermal analysis (DTA). Four new nanocomplexes were obtained in the form of powder Er(Btfa)3Phen, Er(Btfa)3Bipy, Nd(Btfa)3Phen and Nd(Btfa)3Bipy and showed different coloring of the isolated binders, which suggests the occurrence of coordination between ions lanthanide and organic binders. The elementary analysis showed an excellent agreement between the experimental values and the calculated theoretical values, with an average error of 0.1% to 2%, which may possibly be related to the established stoichiometry. Comparing the absorption spectra in the UV-Visible region of the free binders with those of the nanocomplexes, it is possible to observe the displacement of the absorption bands of the binders in relation to the bands of the nanocomplexes. This ensures the hypothesis of formation of new nanocomplexes. The structural characteristics are not compatible with the binders. The morphological characteristics showed the high degree of crystallinity of the nanocomplexes. Thermal analysis found that the nanocomplexes are thermally stable up to 100 ° C and the presence of lanthanides increased the initial melting / decomposition temperatures.