New complexes of lighter trivalent lanthanides with indomethacin anti-inflammatory drug: synthesis, thermal properties and spectroscopic study in the solid state.

Solid-state Ln( ind ) 3 compounds, in which H ind is indomethacin, an anti-inflammatory drug, and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, were synthesized and characterized using thermogravimetry (TG), differential thermal analysis (DTA), Fourier transform infrared spectroscopy (FTIR), elemental analysis and complexometric titration with EDTA. The thermal analysis results provided information concerning the thermal stability, dehydration and thermal behavior of the compounds. The theoretical and experimental spectroscopic data suggest that indomethacin coordinates through the carboxylate group to the metals as a chelating ligand.