The unique properties of macroporous, mesoporous, and microporous systems, including their ability to accommodate molecules of different sizes inside their pores and to act as drug delivery systems, have been the object of extensive studies. In this work, mesoporous silica with hexagonal structure was obtained by template synthesis via the sol–gel process. The resulting material was used as support to accommodate the anti-inflammatory agent indomethacin. The alkaline route was used to prepare the mesoporous silica; cetyltrimethylammonium bromide was employed as porogenic agent. The silica particles were functionalized with 3-aminopropyltriethoxysilane alkoxide (APTES) by the sol–gel post-synthesis method. Indomethacin was incorporated into the silica functionalized with APTES and into non-functionalized silica. The resulting systems were characterized by x-ray diffraction (XRD), specific area, infrared spectroscopy, and thermal analyses (TGA). XRD attested to formation of mesoporous silica with hexagonal structure. This structure remained after silica functionalization with APTES and incorporation of indomethacin. Typical infrared spectroscopy vibrations and organic material decomposition during TGA confirmed silica functionalization and drug incorporation. The specific surface area and pore volume of the functionalized material incorporated with indomethacin decreased as compared with the specific surface area and pore volume of the non-functionalized silica containing no drug, suggesting both the functionalizing agent and the drug were present in the silica. Cytotoxicity tests conducted on normal fibroblasts (GM0479A) cells attested that the silica matrix containing indomethacin was less toxic than the free drug.

This study presents the synthesis, structural and luminescence properties for lanthanide metal–organic frameworks (LnMOFs), which belong to the sub-class of coordination polymers. The series of nanosized LnMOFs (Ln = Eu, Gd, Tb, Eu_0.5Gd_0.5, Tb_0.5Gd_0.5 and Eu_0.5Tb_0.5) was prepared by solvothermal synthesis using a modulator (sodium acetate). We investigated the various surface chemistry compositions of the isostructural LnMOFs with a [Ln(btc)] structure (BTC: Benzene-1,3,5-tricarboxylate) by X-ray photoelectron spectroscopy (XPS). The XPS confirmed the mixed-valent Eu³⁺ and Eu²⁺ compounds, and the presence of Tb in both +3 and +4 valence states, and one +3 valency of Gd. A nanostructure of mixed LnMOFs (EuGd, TbGd and EuTb) with a rod-like shape is related to luminescence properties. The MOFs (EuTb and EuGd) presented Comission Internationale de l’Éclairage (CIE) chromaticities of x = 0.666 and y = 0.331, and x = 0.654 and y = 0.348, respectively, in the red region. They were better than the values desired for use in commercial phosphors, which are x = 0.64 and y = 0.35. For [Tb/Gd(btc)], the CIE coordinates were x = 0.334 and y = 0.562, presenting emissions in the green region. Bimetallic LnMOFs are very promising UV light sensors for biological applications.