Thermal, spectroscopic and biological studies on solid ibuprofen complexes of heavy trivalent lanthanides and yttrium

Abstract

Heavy lanthanide complexes (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) and yttrium (III) complexes with ibuprofen ligands (Hibu) were synthesized and characterized by simultaneous thermogravimetric and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), attenuated total reflection midinfrared spectroscopy (ATR-MIR), complexometric titration, X-ray powder diffraction (XRD) in order to determine stoichiometry, thermal stability and the ligand coordination modes of the compounds. The volatiles released were also analyzed by online coupled thermogravimetry-infrared spectroscopy evolved gas analysis (TG-EGA-MIR), to identify the main product resulting from the heating of terbium complex. In addition, ibuprofen and the synthesized compounds were tested to assess cytotoxic/proliferative and anti-inflammatory activity. The results of the cytotoxicity assays showed that compounds [Yb(ibu) 3 ], [Lu(ibu) 3 ] and [Y(ibu) 3 ] decreased the cytotoxic activity of ibuprofen. Furthermore, [Yb(ibu) 3 ] and [Lu(ibu) 3 ] exhibited a significant anti-inflammatory profile, superior to that of ibuprofen. Under the stimulatory effect of lipopolysaccharide, these compounds displayed anti-inflammatory activity characterized by low TNF-␣ and H 2 O 2 production and high IL-10 production, emerging as interesting alternatives for further biological applications.

Crude leaf extracts of Piperaceae species downmodulate inflammatory responses by human monocytes

“…Another important finding was the capacity of all extracts to prevent the production of IL-10 by monocytes, as well as by monocytes treated with ketoprofen. Usually, the production of IL-10 is increased by LPS-stimulated monocytes [ 51 , 52 ], probably due to an effort of cells to control the inflammation. Indeed, sepsis is associated with a monocyte hyporesponsiveness to LPS that appears to be proportional to the severity of sepsis and release of cytokines such as PGE2, TGF-β, and IL-10 [ 53 ].…”

Yttrium(iii) coordination polymer micro/nanospheres with single ligand and dual ligands

“…In the last few decades, there has been considerable interest in rare-earth-based coordination polymers (RE-CP). Inorganicorganic hybrid materials are very important because they have many potential applications in a broad range of elds such as chemical sensing, lighting and display [1][2][3][4][5][6][7] bioapplications, 8,9 and thermometric probes. 1,10 Lanthanide materials are very useful in many applications.…”

Ion-exchange resin as a new tool for characterisation of coordination compounds and MOFs by NMR spectroscopy

“…Many compounds bearing transition metal and lanthanoid cations have relevant applications in chemistry and apart from being present in biological systems, these ions can also combine with thousands of organic ligands, to result in compounds that deserve intense scientific study. [1][2][3] The paramagnetic effect limits investigation by nuclear magnetic resonance (NMR) and limits the use of this very elucidative technique to shed light on chemical structures. 4 The usual strategy to analyse complexes containing paramagnetic ions is to add a strong acid or base to the complex, to cleave the M-L bonds and to release the ion and the ligands.…”