The aim of this thesis was the synthesis and characterization of luminescent lanthanide complexes and their immobilization in the mesoporous material MCM-41. In the first approach, complexes of the type Eu(NTA)3L2 were studied, where NTA is 1-(2-naphthoyl)-3,3,3-trifluoroacetonate, L2 is a chelating (bidentate) nitrogen ligand derived from pyrazolylpyridine and L is a monodentate ligand (ethyl[3-(2-pyridyl)-1-pyrazolyl]acetate, water, pyridine and phenyl methyl sulfoxide). Some of these ligands were immobilized and/or impregnated in MCM-41, and the fragment Eu(NTA)3 was subsequently complexed. In the second approach, the effect of the counter ion in the complex C[Eu(NTA)4] was studied, using the cations (C+): tetrabutylammonium [NBu4]+, 1-butyl-3-methylimidazolium [C4mim]+ and 1-butyl-3-methylpyridinium [C4mpy]+. The anion [Eu(NTA)4]- was immobilized in MCM-41 derivatized with 1-propyl-3-methylimidazolium groups. All complexes were characterized by elemental and thermogravimetric analyses, vibrational (Infrared and Raman) and nuclear magnetic resonance spectroscopies, and the derivatized materials were additionally studied by Xray powder diffraction and solid state NMR. The photoluminescence properties of the complexes and the derivatized materials were studied, and in order to analyze the results, in some cases, analogous gadolinium-containing compounds were prepared and characterized.