Matias Funes - Academia.edu (original) (raw)
Papers by Matias Funes
Photodiagnosis and Photodynamic Therapy, 2017
Porophyllum obscurum hexane extract possesses antifungal activity under UV-A light Four thiophe... more Porophyllum obscurum hexane extract possesses antifungal activity under UV-A light Four thiophenes were identified as the main compounds responsible for the activity The activity was demonstrated against 25 Candida strains from patients with OPC PDT with natural PS has emerged as an alternative to conventional treatments A correlation between thiophenes concentration and the activity was
Fitoterapia, Jan 24, 2018
We report here for the first time antinociceptive effects of extracts from Baccharis flabellata. ... more We report here for the first time antinociceptive effects of extracts from Baccharis flabellata. Two extracts in this analysis, one obtained in summer and the other during winter time. Our results indicate that both extract show strong antinociceptive effects, being the extracts obtained during the summer significantly more active. Our results suggest that this activity is mainly due to the presence of the diene-acid clerodane ent-15,16-epoxy-19-hydroxy-1,3,13(16),14-clerodatetraen-18-oic acid (DAC) and its dimer called DACD. Employing naloxone as an antagonist of opioid receptors, we demonstrated that both compounds act on opioid receptors, being the antinociceptive effect of DACD stronger than DAC. Thus, the antinociceptive activity of DACD was almost two times stronger than DAC (44.8 over 24.6 s in the hot-plate test) after one hour of treatments. In order to better understand the mechanism of action at molecular level of these compounds, we conducted a molecular modeling study a...
J Phys Chem C, 2009
Charge separation has been investigated at Pd-porphyrin (Pd-P)/TiO 2 interfaces by surface photov... more Charge separation has been investigated at Pd-porphyrin (Pd-P)/TiO 2 interfaces by surface photovoltage spectroscopy in the Kelvin-probe arrangement. Ultrathin nanoporous TiO 2 layers were covered with Pd-P molecules from highly diluted organic solution starting from the submonolayer range. Mechanisms of charge separation including charge separation in TiO 2 nanoparticles, an ionic transport component, and injection of electrons into TiO 2 from states of solitary Pd-P molecules not interacting with each other on the surface and from Pd-P molecules interacting with each other and with TiO 2 were identified. A developed model for the simulation of surface photovoltage spectra considered mechanisms of charge separation and respective recombination paths. Characteristic charge separation lengths and recombination coefficients were obtained for the different components of separated charge.
La presente invención está relacionada con un material de transferencia fotoeléctrico y electro-ó... more La presente invención está relacionada con un material de transferencia fotoeléctrico y electro-óptico y su método de manufactura, el elemento de transferencia y su método de manufactura, especialmente apto para su aplicación en celdas solares orgánicas y dispositivos que cambien de color por la aplicación de un voltaje (electrocrómicos).
Photochemistry and Photobiology, 2007
The 3,3¢, 4¢,7 tetrahydroxiflavone (fisetin) is a natural therapeutically active and fluorescent ... more The 3,3¢, 4¢,7 tetrahydroxiflavone (fisetin) is a natural therapeutically active and fluorescent polyhydroxyflavone, with important spectroscopic and biological behavior. Fisetin shows dual emission, with a normal band (N) from the S 1 fi S 0 transition and the one generated in the excited state (phototautomer; PT) from the intramolecular proton transfer (ESIPT) process. The influence of different interfaces on the ESIPT process of fisetin was investigated in reverse micelles media (RMs) made of the anionic sodium 1,4-bis (2-ethylhexyl) sulfosuccinate (AOT) and cationic benzyl n-hexadecyl dimethylammonium chloride (BHDC) surfactants, in benzene. The studies were carried out by absorption, emission spectroscopy, steady-state anisotropy and time-resolved fluorescence measurements. Fisetin behavior was also investigated in homogeneous media with special emphasis in water and benzene, which are the polar core and the organic pseudofase in the RMs, respectively. In addition, the effect of concentration in benzene and the variation of the pH in water were studied. Fluorescence lifetime measurements show that in water the ESIPT process is independent on the concentration, while in benzene it was possible to detect fluorescent aggregate species (Nas) formed in the ground state. The effect of the pH in water allowed us to identify the anionic fisetin (A)) emission. The studies in RMs show that fisetin interacts specifically with the head of the surfactants, which always results in diminishing the emission of the PT. Also the formation of A) is detected particularly at W 0 > 0. Appreciable high anisotropy values are obtained in RMs, as compared with those in fluid homogeneous media, which are independent of the water content confirming that fisetin molecules are anchored in the anionic as well as in the cationic interfaces.
Environmental Science & Technology, 2009
Spectroscopic and photodynamic properties of polymeric films bearing porphyrin units have been st... more Spectroscopic and photodynamic properties of polymeric films bearing porphyrin units have been studied in both solution containing photooxidizable substrates and in vitro on Escherichia coli and Candida albicans microorganisms. The films were formed by electrochemical polymerization of 5,10,15,20-tetra(4-N,N-diphenylaminophenyl)porphyrin (H 2 P-film) and its complex with Pd(II) (PdP-film) on optically transparent indium tin oxide (ITO) electrodes. Absorption spectroscopic studies show the characteristic Soret and Q bands of the porphyrin in the visible region and a band at ∼350 nm corresponding to the tetraphenylbenzidine units. Upon excitation, the H 2 P-film exhibits two bands of fluorescence emission from porphyrin, while it is not detected using PdP-film. The singlet molecular oxygen, O 2 (1 ∆ g), productions of these surfaces were evaluated using 9,10-dimethylanthracene in N,N-dimethylformamide. Also, the photodynamic activity was compared in solutions of L-tryptophan. Under these conditions, oxidation of these substrates takes place indicating an efficient photodynamic action of both polymeric films. In vitro investigations show that these films produce photosensitized inactivation of microbial cells in aqueous suspensions. These films exhibit a photosensitizing activity causing a ∼3 log decrease of E. coli and ∼2.5 log of C. albicans cellular survival after 30 min of irradiation with visible light. The photodynamic effect of the surfaces was also tested by growth delay experiments. The results indicate that porphyrins immobilized on electropolymeric films are interesting and versatile photodynamic surfaces to inactivate microorganisms in liquid suspensions.
Electrochimica Acta, 2011
The formation and characterization of novel polymer modified Pt and ITO electrodes obtained by el... more The formation and characterization of novel polymer modified Pt and ITO electrodes obtained by electropolymerization is depicted. The presences of porphyrin, a powerful optical and redox active center, together with carbazole, a well-known hole-transporting material, confer to the polymer electric and optical activity, with potential application in the development of organic optoelectronic devices. 5,10,15,20-Tetrakis[3-(N-ethylcarbazoyl)]porphyrin form conductive, stable and reproducible electropolymer
Electrochimica Acta, 2010
Free base and Pd(II) 5,10,15,20-tetrakis(4-N,N-diphenylaminophenyl)porphyrin form conductive, sta... more Free base and Pd(II) 5,10,15,20-tetrakis(4-N,N-diphenylaminophenyl)porphyrin form conductive, stable and reproducible electropolymer films. The combined electrochemical and spectroscopic studies show that the electropolymerization mechanism involves the dimerization of triphenylamine units, conducting the formation of a tridimensional structure where porphyrin cores are in a perpendicular fashion that avoids aggregation. Switching between the polymer neutral and oxidized states produced color changes which can
Photodiagnosis and Photodynamic Therapy, 2017
Porophyllum obscurum hexane extract possesses antifungal activity under UV-A light Four thiophe... more Porophyllum obscurum hexane extract possesses antifungal activity under UV-A light Four thiophenes were identified as the main compounds responsible for the activity The activity was demonstrated against 25 Candida strains from patients with OPC PDT with natural PS has emerged as an alternative to conventional treatments A correlation between thiophenes concentration and the activity was
Fitoterapia, Jan 24, 2018
We report here for the first time antinociceptive effects of extracts from Baccharis flabellata. ... more We report here for the first time antinociceptive effects of extracts from Baccharis flabellata. Two extracts in this analysis, one obtained in summer and the other during winter time. Our results indicate that both extract show strong antinociceptive effects, being the extracts obtained during the summer significantly more active. Our results suggest that this activity is mainly due to the presence of the diene-acid clerodane ent-15,16-epoxy-19-hydroxy-1,3,13(16),14-clerodatetraen-18-oic acid (DAC) and its dimer called DACD. Employing naloxone as an antagonist of opioid receptors, we demonstrated that both compounds act on opioid receptors, being the antinociceptive effect of DACD stronger than DAC. Thus, the antinociceptive activity of DACD was almost two times stronger than DAC (44.8 over 24.6 s in the hot-plate test) after one hour of treatments. In order to better understand the mechanism of action at molecular level of these compounds, we conducted a molecular modeling study a...
J Phys Chem C, 2009
Charge separation has been investigated at Pd-porphyrin (Pd-P)/TiO 2 interfaces by surface photov... more Charge separation has been investigated at Pd-porphyrin (Pd-P)/TiO 2 interfaces by surface photovoltage spectroscopy in the Kelvin-probe arrangement. Ultrathin nanoporous TiO 2 layers were covered with Pd-P molecules from highly diluted organic solution starting from the submonolayer range. Mechanisms of charge separation including charge separation in TiO 2 nanoparticles, an ionic transport component, and injection of electrons into TiO 2 from states of solitary Pd-P molecules not interacting with each other on the surface and from Pd-P molecules interacting with each other and with TiO 2 were identified. A developed model for the simulation of surface photovoltage spectra considered mechanisms of charge separation and respective recombination paths. Characteristic charge separation lengths and recombination coefficients were obtained for the different components of separated charge.
La presente invención está relacionada con un material de transferencia fotoeléctrico y electro-ó... more La presente invención está relacionada con un material de transferencia fotoeléctrico y electro-óptico y su método de manufactura, el elemento de transferencia y su método de manufactura, especialmente apto para su aplicación en celdas solares orgánicas y dispositivos que cambien de color por la aplicación de un voltaje (electrocrómicos).
Photochemistry and Photobiology, 2007
The 3,3¢, 4¢,7 tetrahydroxiflavone (fisetin) is a natural therapeutically active and fluorescent ... more The 3,3¢, 4¢,7 tetrahydroxiflavone (fisetin) is a natural therapeutically active and fluorescent polyhydroxyflavone, with important spectroscopic and biological behavior. Fisetin shows dual emission, with a normal band (N) from the S 1 fi S 0 transition and the one generated in the excited state (phototautomer; PT) from the intramolecular proton transfer (ESIPT) process. The influence of different interfaces on the ESIPT process of fisetin was investigated in reverse micelles media (RMs) made of the anionic sodium 1,4-bis (2-ethylhexyl) sulfosuccinate (AOT) and cationic benzyl n-hexadecyl dimethylammonium chloride (BHDC) surfactants, in benzene. The studies were carried out by absorption, emission spectroscopy, steady-state anisotropy and time-resolved fluorescence measurements. Fisetin behavior was also investigated in homogeneous media with special emphasis in water and benzene, which are the polar core and the organic pseudofase in the RMs, respectively. In addition, the effect of concentration in benzene and the variation of the pH in water were studied. Fluorescence lifetime measurements show that in water the ESIPT process is independent on the concentration, while in benzene it was possible to detect fluorescent aggregate species (Nas) formed in the ground state. The effect of the pH in water allowed us to identify the anionic fisetin (A)) emission. The studies in RMs show that fisetin interacts specifically with the head of the surfactants, which always results in diminishing the emission of the PT. Also the formation of A) is detected particularly at W 0 > 0. Appreciable high anisotropy values are obtained in RMs, as compared with those in fluid homogeneous media, which are independent of the water content confirming that fisetin molecules are anchored in the anionic as well as in the cationic interfaces.
Environmental Science & Technology, 2009
Spectroscopic and photodynamic properties of polymeric films bearing porphyrin units have been st... more Spectroscopic and photodynamic properties of polymeric films bearing porphyrin units have been studied in both solution containing photooxidizable substrates and in vitro on Escherichia coli and Candida albicans microorganisms. The films were formed by electrochemical polymerization of 5,10,15,20-tetra(4-N,N-diphenylaminophenyl)porphyrin (H 2 P-film) and its complex with Pd(II) (PdP-film) on optically transparent indium tin oxide (ITO) electrodes. Absorption spectroscopic studies show the characteristic Soret and Q bands of the porphyrin in the visible region and a band at ∼350 nm corresponding to the tetraphenylbenzidine units. Upon excitation, the H 2 P-film exhibits two bands of fluorescence emission from porphyrin, while it is not detected using PdP-film. The singlet molecular oxygen, O 2 (1 ∆ g), productions of these surfaces were evaluated using 9,10-dimethylanthracene in N,N-dimethylformamide. Also, the photodynamic activity was compared in solutions of L-tryptophan. Under these conditions, oxidation of these substrates takes place indicating an efficient photodynamic action of both polymeric films. In vitro investigations show that these films produce photosensitized inactivation of microbial cells in aqueous suspensions. These films exhibit a photosensitizing activity causing a ∼3 log decrease of E. coli and ∼2.5 log of C. albicans cellular survival after 30 min of irradiation with visible light. The photodynamic effect of the surfaces was also tested by growth delay experiments. The results indicate that porphyrins immobilized on electropolymeric films are interesting and versatile photodynamic surfaces to inactivate microorganisms in liquid suspensions.
Electrochimica Acta, 2011
The formation and characterization of novel polymer modified Pt and ITO electrodes obtained by el... more The formation and characterization of novel polymer modified Pt and ITO electrodes obtained by electropolymerization is depicted. The presences of porphyrin, a powerful optical and redox active center, together with carbazole, a well-known hole-transporting material, confer to the polymer electric and optical activity, with potential application in the development of organic optoelectronic devices. 5,10,15,20-Tetrakis[3-(N-ethylcarbazoyl)]porphyrin form conductive, stable and reproducible electropolymer
Electrochimica Acta, 2010
Free base and Pd(II) 5,10,15,20-tetrakis(4-N,N-diphenylaminophenyl)porphyrin form conductive, sta... more Free base and Pd(II) 5,10,15,20-tetrakis(4-N,N-diphenylaminophenyl)porphyrin form conductive, stable and reproducible electropolymer films. The combined electrochemical and spectroscopic studies show that the electropolymerization mechanism involves the dimerization of triphenylamine units, conducting the formation of a tridimensional structure where porphyrin cores are in a perpendicular fashion that avoids aggregation. Switching between the polymer neutral and oxidized states produced color changes which can