48 documents found, page 1 of 5
Enhancing bacterial photodynamic inactivation through combined action of potass...
Gamelas, Sara R. D.; Bartolomeu, Maria; Vieira, Cátia; Faustino, Maria A. F.; Tomé, João P. C.; Tomé, Augusto C.; Almeida, AdelaideInfectious diseases remain a leading cause of death all around the world. Over the last three decades, the alarming and escalating emergence of antibiotic-resistant bacterial strains has caused some concern among the scientific community [1,2]. Photodynamic inactivation (PDI) emerges as an alternative for inactivating microorganisms, including bacteria [1–3]. The use of phthalocyanine (Pc) derivatives as photos...
Spherical and rod shaped mesoporous nanosilicas for cancer- targeted and photos...
Trindade, Tito; Borzęcka, Wioletaa; Pereira, Patrícia M. R; Fernandes, Rosa; Torres, Tomás; Tomé, João P. C.Mesoporous silica nanoparticles (MSNPs) have attracted much attention in many biomedical applications. One of the fields in which smart functional nanosystems have found wide application is cancer treatment. Here, we present new silica nanoparticle-based systems which have been explored as efficient vehicles to transport and deliver photosensitizers (PSs) into tumor tissues during photodynamic therapy (PDT). In...
Encapsulation of glycosylated porphyrins in silica nanoparticles to enhance the...
Borzęcka, Wioleta; Pereira, Patrícia M. R.; Fernandes, Rosa; Trindade, Tito; Torres, Tomás; Tomé, João P. C.In this study, we encapsulated S-galactosylated and S-glucosylated porphyrins (Pors) into amorphous silica nanoparticles (SNPs) to enhance the photodynamic therapy (PDT) activity. The resulting galactoand gluco-nanoformulations were demonstrated to be spherical in shape with diameters of 197.3 29.0 nm and 128.3 22.2 nm. The galacto- and gluco-nanoparticles (NPs) were able to produce a high amount of singlet oxy...
Phthalocyanine-functionalized magnetic silica nanoparticles as anion chemosensors
Rodrigues, João M. M.; Farinha, Andreia S. F.; Zhi Lin; Cavaleiro, José A. S.; Tomé, Augusto C.; Tomé, João P. C.Anionic species are one of the most common pollutants in residual and freshwaters. The presence of anthropogenic anions in water drastically increases the toxicity to living beings. Here, we report the preparation of a new optical active material based on tri(tosylamino)phthalocyanines grafted to ferromagnetic silica nanoparticles for anion detection and removal. The new unsymmetrical phthalocyanines (Pcs) prov...
Photocatalytic degradation of methyl orange mediated by a silica coated nanomag...
Castro, Kelly A. D. F.; Rodrigues, João M. M.; Faustino, Maria A.; Tomé, João P. C.; Cavaleiro, José A. S.; Neves, Maria da Graça P. M. S.The photocatalytic activity of a silica coated nanomagnet porphyrin hybrid (NPH) and of the corresponding porphyrin precursors (H2P and ZnP) was evaluated in the degradation of the methyl orange dye (MO) under visible light irradiation. The catalytic degradation of MO was performed under air, in the absence and in the presence of aqueous hydrogen peroxide. The results show that the hybrid NPH was the most effec...
Multifunctionality in an Ion-Exchanged Porous Metal-Organic Framework
Vilela, Sérgio M. F.; Navarro, Jorge A. R.; Barbosa, Paula; Mendes, Ricardo F.; Pérez-Sánchez, Germán; Nowell, Harriott; Ananias, DuartePorous robust materials are typically the primary selection of several industrial processes. Many of these compounds are, however, not robust enough to be used as multifunctional materials. This is typically the case of Metal-Organic Frameworks (MOFs) which rarely combine several different excellent functionalities into the same material. In this report we describe the simple acid-base postsynthetic modificatio...
Synthesis, Characterization and Photodynamic Activity against Bladder Cancer Ce...
Gomes, Ana T. P. C.; Fernandes, Rosa; Ribeiro, Carlos F. M.; Tomé, João P. C.; Neves, Maria G. P. M. S.; Silva, Fernando de C. da; Ferreira, Vítor F.Novel triazole-porphyrin derivatives (TZ-PORs) were synthesized through the Heck reaction and then incorporated into polyvinylpyrrolidone (PVP) micelles. After verifying that this incorporation did not compromise the photophysical and chemical features of TZ-PORs as photosensitizers, the phototoxicity of the formulations towards cancer cells was screened. Biological studies show high photodynamic activity of al...
Thiophene- and carbazole-substituted N-Methyl-Fulleropyrrolidine acceptors in P...
Gaspar, Hugo; Figueira, Flávio; Strutyński, Karol; Melle-Franco, Manuel; Ivanou, Dzmitry; Tomé, João P. C.; Pereira, Carlos M.; Pereira, LuizThe impact of fullerene side chain functionalization with thiophene and carbazole groups on the device properties of bulk-heterojunction polymer:fullerene solar cells is discussed through a systematic investigation of material blends consisting of the conjugated polymer poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3‴-di(2-octyldodecyl)-2,2′;5′,2″;5″,2‴-quaterthiophen-5,5‴-diyl)] (PffBT4T-2OD) as do...
Multicharged Phthalocyanines as Selective Ligands for G-Quadruplex DNA Structures
Ramos, Catarina I. V.; Almeida, Susana P.; Lourenço, Leandro M. O.; Pereira, Patrícia M. R.; Fernandes, Rosa; Faustino, M. Amparo F.; Tomé, João P. C.The stabilization of G-Quadruplex DNA structures by ligands is a promising strategy for telomerase inhibition in cancer therapy since this enzyme is responsible for the unlimited proliferation of cancer cells. To assess the potential of a compound as a telomerase inhibitor, selectivity for quadruplex over duplex DNA is a fundamental attribute, as the drug must be able to recognize quadruplex DNA in the presence...
PffBT4T-2OD based solar cells with Aryl-Substituted N-Methyl-Fulleropyrrolidine...
Gaspar, Hugo; Figueira, Flávio; Strutyński, Karol; Melle-Franco, Manuel; Ivanou, Dzmitry; Tomé, João P. C.; Pereira, Carlos M.; Pereira, LuizNovel C<sub>60</sub> and C<sub>70</sub> <i>N</i>-methyl-fulleropyrrolidine derivatives, containing both electron withdrawing and electron donating substituent groups, were synthesized by the well-known Prato reaction. The corresponding highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) energy levels were determined by cyclic voltammetry, from the onset oxidation and reduction p...