Publications by authors named "Maria C F C Felinto"

Article Synopsis
  • New tetrakis Eu and Gd β-diketonate complexes with benzimidazolium as a counterion were synthesized using a one-pot method, and one specific complex was incorporated into a PMMA matrix showing excellent photonic features.
  • Characterization techniques like ESI-MS, FTIR, and X-ray diffraction were used to analyze the complexes, revealing unique intermolecular interactions and stability of the PMMA-doped material at high temperatures.
  • The study highlighted that the materials exhibited strong photoluminescence with significant red emission when exposed to various UV wavelengths and sunlight, suggesting their potential as efficient light-converting molecular devices.
View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on creating and characterizing water-dispersible Eu/Mn co-doped ZnSe@ZnS quantum dots (QDs) for biomedical cellular imaging applications, highlighting their interaction with cells and their optical properties.
  • The QDs demonstrated high biocompatibility (over 85% cell viability) and a unique ability to emit tunable fluorescence colors, which can be controlled by adjusting the concentration of dopants.
  • The QDs were mostly taken up by macrophage cells via macropinocytosis, maintaining effective internalization for up to 24 hours, making them promising candidates for advanced fluorescent bionanoprobes in biomedicine.
View Article and Find Full Text PDF

Luminescent inorganic materials are used in several technological applications such as light-emitting displays, white LEDs for illumination, bioimaging, and photodynamic therapy. Usually, inorganic phosphors (e.g.

View Article and Find Full Text PDF

The synthesis of 1-benzyl-2-((2-Aminoethyl) amino)-5-oxopyrrolidine-3,4-diyl diacetate (boad), an oxopyrrolidine type ligand; designed to coordinate lanthanides (Eu and Tb) to get luminescent material. The target complexes showed good photoluminescence properties, which indicate that this type of compound can be used as sensitizers having luminescence for the green (Tb) and red (Eu) emission. The obtained results revealed that sensitizer efficiency can be improved by adding ligands like acac (Eu(acac), which has also enhanced the luminescence quantum output and period for Eu ions.

View Article and Find Full Text PDF
Article Synopsis
  • The paper explores the development and properties of new hybrid materials created by attaching EDTA-lanthanide complexes to chitosan surfaces, both in their natural state and after crosslinking with epichlorohydrin.
  • The emission spectra revealed strong light emission from europium and terbium ions, with improved efficiency when using diketonate ligands due to the antenna effect.
  • The study concluded that crosslinked chitosan matrices show promising potential for applications in molecular light conversion devices, thanks to their enhanced emission quantum efficiency.
View Article and Find Full Text PDF
Article Synopsis
  • The odd-even effect was observed in luminescent Eu complexes with various dicarboxylate ligands for the first time, demonstrating a unique relationship between the molecular structure and luminescent properties.
  • The dehydration temperatures of these complexes exhibited a zigzag pattern based on the carbon chain length of the ligands, showcasing the odd-even effect.
  • The paper introduces the ghost-atom model to explain changes in luminescence intensity parameters and discusses how water molecules impact the luminescence of these complexes.
View Article and Find Full Text PDF

Temperature measurements ranging from a few degrees to a few hundreds of Kelvin are of great interest in the fields of nanomedicine and nanotechnology. Here, we report a new ratiometric luminescent thermometer using thermally excited state absorption of the Eu(3+) ion. The thermometer is based on the simple Eu(3+) energy level structure and can operate between 180 and 323 K with a relative sensitivity ranging from 0.

View Article and Find Full Text PDF

The design of bifunctional magnetic luminescent nanomaterials containing Fe3O4 functionalized with rare earth ion complexes of calixarene and β-diketonate ligands is reported. Their preparation is accessible through a facile one-pot method. These novel Fe3O4@calix-Eu(TTA) (TTA = thenoyltrifluoroacetonate) and Fe3O4@calix-Tb(ACAC) (ACAC = acetylacetonate) magnetic luminescent nanomaterials show interesting superparamagnetic and photonic properties.

View Article and Find Full Text PDF

Amino-functionalized luminescent silica particles were investigated for use in immunoassays. The particles were prepared by the Stöber method where the [Eu(TTA)3(H2O)2] complex (TTA: 3-thenoyltrifluoroacetonate) was incorporated into silica particles during the hydrolysis and condensation of TEOS: tetraethylorthosilicate. Then, the amino groups were introduced in the particle surface using APTS: 3-aminopropyltriethoxisilane.

View Article and Find Full Text PDF

The formation of complexes involving p-tert-butylcalix[6]arene with neutral and charged species has been investigated by tandem mass spectrometry combined with electrospray ionization. Complexes of p-tert-butylcalix[6]arene with NH4+ ions were observed in the ratios 1:1, 2:1, and 3:1, together with the complexes of p-tert-butylcalix[6]arene with NH4OH and Na+ ions in the ratios 1:1:1, 2:1:1, and 3:1:1. A single 1:1 complex of p-tert-butylcalix[6]arene with Na+ ions was observed.

View Article and Find Full Text PDF