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Marino N.,Laboratory of Photochemistry | Perez-Lloret M.,Laboratory of Photochemistry | Blanco A.R.,SIFI S.p.A. | Venuta A.,University of Naples Federico II | And 2 more authors.
Journal of Materials Chemistry B | Year: 2016

A novel photoresponsive molecular hybrid has been embedded in poly(lactic-co-glycolic acid) (PLGA) to give an antibacterial polymeric film generating nitric oxide (NO) under visible light, with concomitant fluorescence reporting of NO release. The molecular hybrid integrates a nitroaniline NO photodonor and a coumarin latent fluorophore in the same molecular skeleton and results in quite homogeneous distribution in the polymer matrix where it preserves well the photobehavior exhibited in solution. The doped PLGA film shows an excellent optical transparency and can be excited by visible light leading to the production of NO and the parallel fluorescence revival of the coumarin fluorophore, which acts as an optical NO reporter. Photogenerated NO diffuses out of the polymer film, can be transferred to a biological milieu and induces remarkable antibacterial activity against Escherichia coli. © The Royal Society of Chemistry 2016.


Di Bari I.,Laboratory of Photochemistry | Picciotto R.,Laboratory of Photochemistry | Granata G.,CNR Institute of Biomolecular Chemistry | Blanco A.R.,SIFI S.p.A. | And 2 more authors.
Organic and Biomolecular Chemistry | Year: 2016

A hydrophobic N-dodecyl-3-(trifluoromethyl)-4-nitrobenzenamine has been synthesized as a suitable NO photodonor and encapsulated in a nanocontainer based on a polycationic calix[4]arene derivative, leading to a supramolecular micellar-like nanoassembly ca. 45 nm in diameter. Visible light excitation of this nanoconstruct triggers NO generation with an efficiency remarkably higher than that observed for the free NO photoreleaser. This amplified NO release results in considerable antibacterial activity against Staphylococcus aureus (ATCC 6538) and Pseudomonas aeruginosa (ATCC 9027) as representative Gram positive and Gram negative bacteria, respectively. © 2016 The Royal Society of Chemistry.


Marino N.,Laboratory of Photochemistry | Petralia S.,STMicroelectronics | Perez-Lloret M.,Laboratory of Photochemistry | Mosinger J.,Charles University | And 2 more authors.
Journal of Materials Chemistry B | Year: 2016

We report herein a photoresponsive nanoplatform that delivers nitric oxide (NO) on demand, achieved by the covalent functionalization of graphene oxide (GO) with an amino-terminated nitric oxide (NO) photodonor (NOP1). The resulting GO-NOP1 hybrid nanomaterial is dispersible in water, is very stable in the dark and has been thoroughly characterized by SEM, TEM, AFM, XRD, FTIR and UV-Vis absorption spectroscopy. Photolysis experiments demonstrate that the photodecomposition of the NO photoreleaser integrated into the GO scaffold occurs with an efficiency similar to that observed for a free model compound, ruling out any significant quenching effect (i.e. photoinduced energy/electron transfer) and accounting for the excellent preservation of its photochemical properties upon grafting. A combination of direct amperometric detection and indirect measurements based on a fluorometric assay prove that the remote-controlled release of NO from the GO-NOP1 nanoplatform is exclusively regulated by visible light stimuli. © 2016 The Royal Society of Chemistry.


Szabelski P.,Maria Curie Sklodowska University | De Feyter S.,Laboratory of Photochemistry | Drach M.,Catholic University of Leuven | Lei S.,Harbin Institute of Technology
Langmuir | Year: 2010

A lattice Monte Carlo (MC) model was proposed with the aim of understanding the factors affecting the chiral self-assembly of tripod-shaped molecules in two dimensions. To that end a system of flat symmetric molecules adsorbed on a triangular lattice was simulated by using the canonical ensemble method. Special attention was paid to the influence of size and composition of the building block on the morphology of the adsorbed overlayer. The obtained results demonstrated a spontaneous self-assembly into extended chiral networks with hexagonal cavities, highlighting the ability of the model to reproduce basic structural features of the corresponding experimental systems. The simulated assemblies were analyzed with respect to their structural and energetic properties resulting in quantitative estimates of the unit cell parameters and mean potential energy of the adsorbed layer. The predictive potential of the model was additionally illustrated by comparison of the obtained superstructures with the recent STM images that have been recorded for different organic tripod-shaped molecules adsorbed at the liquid/pyrolytic graphite interface. © 2010 American Chemical Society.


Maiolino S.,University of Naples Federico II | Moret F.,University of Padua | Conte C.,University of Naples Federico II | Fraix A.,Laboratory of Photochemistry | And 5 more authors.
Nanoscale | Year: 2015

In the attempt to develop novel concepts in designing targeted nanoparticles for combination therapy of cancer, we propose here CD44-targeted hyaluronan-decorated double-coated nanoparticles (dcNPs) delivering the lipophilic chemotherapeutic docetaxel (DTX) and an anionic porphyrin (TPPS4). dcNPs are based on electrostatic interactions between a negative DTX-loaded nanoscaffold of poly(lactide-co-glycolide), a polycationic shell of polyethyleneimine entangling negatively-charged TPPS4 and finally decorated with hyaluronan (HA) to promote internalization through CD44 receptor-mediated endocytosis. DTX/TPPS4-dcNPs, prepared through layer-by-layer deposition, showed a hydrodynamic diameter of around 180 nm, negative zeta potential and efficient loading of both DTX and TPPS4. DTX/TPPS4-dcNPs were freeze-dried with trehalose giving a powder that could be easily dispersed in different media. Excellent stability of dcNPs in specific salt- and protein-containing media was found. Spectroscopic behavior of DTX/TPPS4-dcNPs demonstrated a face-to-face arrangement of the TPPS4 units in non-photoresponsive H-type aggregates accounting for an extensive aggregation of the porphyrin embedded in the shell. Experiments in MDA-MB-231 cells overexpressing the CD44 receptor demonstrated a 9.4-fold increase in the intracellular level of TPPS4 delivered from dcNPs as compared to free TPPS4. Light-induced death increased tremendously in cells that had been treated with a combination of TPPS4 and DTX delivered through dcNPs as compared with free drugs, presumably due to efficient uptake and co-localization inside the cells. In perspective, the strategy proposed here to target synergistic drug combinations through HA-decorated nanoparticles seems very attractive to improve the specificity and efficacy of cancer treatment. This journal is © The Royal Society of Chemistry.


Kandoth N.,Laboratory of Photochemistry | Vittorino E.,Laboratory of Photochemistry | Sciortino M.T.,Messina University | Parisi T.,Messina University | And 3 more authors.
Chemistry - A European Journal | Year: 2012

We have developed a supramolecular nanoassembly capable of inducing remarkable levels of cancer cell mortality through a bimodal action based on the simultaneous photogeneration of nitric oxide (NO) and singlet oxygen ( 1O 2). This was achieved through the appropriate incorporation of an anionic porphyrin (as 1O 2 photosensitizer) and of a tailored NO photodonor in different compartments of biocompatible nanoparticles based on cationic amphiphilic cyclodextrins. The combination of steady-state and time-resolved spectroscopic techniques showed the absence of significant intra- and interchromophoric interaction between the two photoactive centers embedded in the nanoparticles, with consequent preservation of their photodynamic properties. Photodelivery of NO and 1O 2 from the nanoassembly on visible light excitation was unambiguously demonstrated by direct and real-time monitoring of these transient species through amperometric and time-resolved infrared luminescence measurements, respectively. The typical red fluorescence of the porphyrin units was essentially unaffected in the bichromophoric nanoassembly, allowing its localization in living cells. The convergence of the dual therapeutic action and the imaging capacities in one single structure makes this supramolecular architecture an appealing, multifunctional candidate for applications in biomedical research. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


PubMed | Laboratory of Photochemistry
Type: Journal Article | Journal: Chemistry (Weinheim an der Bergstrasse, Germany) | Year: 2012

We have developed a supramolecular nanoassembly capable of inducing remarkable levels of cancer cell mortality through a bimodal action based on the simultaneous photogeneration of nitric oxide (NO) and singlet oxygen ((1)O(2)). This was achieved through the appropriate incorporation of an anionic porphyrin (as (1)O(2) photosensitizer) and of a tailored NO photodonor in different compartments of biocompatible nanoparticles based on cationic amphiphilic cyclodextrins. The combination of steady-state and time-resolved spectroscopic techniques showed the absence of significant intra- and interchromophoric interaction between the two photoactive centers embedded in the nanoparticles, with consequent preservation of their photodynamic properties. Photodelivery of NO and (1)O(2) from the nanoassembly on visible light excitation was unambiguously demonstrated by direct and real-time monitoring of these transient species through amperometric and time-resolved infrared luminescence measurements, respectively. The typical red fluorescence of the porphyrin units was essentially unaffected in the bichromophoric nanoassembly, allowing its localization in living cells. The convergence of the dual therapeutic action and the imaging capacities in one single structure makes this supramolecular architecture an appealing, multifunctional candidate for applications in biomedical research.

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