Repository logo

Browsing by Author "Carrott, Manuela Ribeiro"

Now showing 1 - 2 of 2
  • Boosting antimicrobial activity of ciprofloxacin by functionalization of mesoporous silica nanoparticles
    Publication . Juan Mora, Blanca de; Filipe, Luís; Forte, Andreia; Santos, Miguel M.; Alves, Celso; Teodoro, Fernando; Pedrosa, Rui; Carrott, Manuela Ribeiro; Branco, Luís C.; Gago, Sandra
    Mesoporous silica nanoparticles (MSNs) are very promising nanomaterials for treating bacterial infections when combined with pharmaceutical drugs. Herein, we report the preparation of two nanomaterials based on the immobilization of ciprofloxacin in mesoporous silica nanoparticles, either as the counter-ion of the choline derivative cation (MSN-[Ch][Cip]) or via anchoring on the surface of amino-group modified MSNs via an amide bond (MSN-Cip). Both nanomaterials were characterized by TEM, FTIR and solution 1H NMR spectroscopies, elemental analysis, XRD and N2 adsorption at 77 K in order to provide the desired structures. No cytotoxicity from the prepared mesoporous nanoparticles on 3T3 murine fibroblasts was observed. The antimicrobial activity of the nanomaterials was determined against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Klebsiella pneumoniae) bacteria and the results were promising against S. aureus. In the case of B. subtilis, both nanom aterials exhibited higher antimicrobial activity than the precursor [Ch][Cip], and in the case of K. pneumoniae they exhibited higher activity than neutral ciprofloxacin.
    2021Journal article Open access Show more
  • Mesoporous silica nanoparticles with manganese and lanthanide salts: synthesis, characterization and cytotoxicity studies
    Publication . Forte, Andreia; Gago, Sandra; Carrott, Manuela Ribeiro; Carrott, Peter; Alves, Celso; Teodoro, Fernando; Pedrosa, Rui; Marrucho, Isabel M.; Branco, Luis C
    Several organic salts based on the combination of two different choline derivative cations and MnCl3−, GdCl4− and TbCl4− as anions were immobilized in mesoporous silica nanoparticles (MSNs) by a two-step synthetic method. Firstly, MSNs were functionalized with choline derivative cations with chloride anions and then the metals were incorporated by the reaction of the chloride with the respective metal chloride salts. These nanomaterials were fully characterized by different characterization techniques such as 1H-NMR, FT-IR, elemental analysis, TEM, TGA, N2 adsorption, XRD and DLS. These characterization data were important to confirm the successful functionalization of the nanomaterials and to access their textural properties and colloidal stability. The final materials were also characterized by ICP-MS that indicated the metal contents. The cytotoxicity profile was evaluated in four different cell lines (3T3, 293T, HepG2 and Caco-2), which shows some relevant differences between the metal organic salts and their immobilized analogues.
    2021Journal article Restricted access Show more