G. G. Aloisi

University of Padova, Padua, Veneto, Italy

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Publications (67)133.27 Total impact

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    ABSTRACT: Commercial clays Cloisites®Na+, 30B and 20A were labelled with the fluorescent dye Rhodamine B and used as fillers of polypropylene in order to prepare composites to be studied with confocal fluorescence microscopy. The dye uptake by clays was monitored by X-ray powder diffraction and spectroscopic analyses and clear evidences of intercalated dye in the organically modified montmorillonites Clo30B and Clo20A were obtained. Clay–Rhodamine B hybrids were investigated by steady-state absorption and emission spectroscopy to explore the effect of dye arrangement on the optical properties. The obtained information was used to rationalize fluorescence behaviour of composites. Confocal fluorescence imaging gave rise to bright fluorescent images of Cloisite aggregated labelled with the dye allowing to easily and directly visualize the 3-D dispersion of the labelled fillers in the polymer matrix in a non-invasive manner. The images were analyzed in terms of size distribution of the fluorescence grains to quantify the dispersion degree. The data indicate that Clo20A is able to homogeneously distribute in the polymer matrix forming a composite material.
    Materials Chemistry and Physics 01/2010; 123:372-377. · 2.07 Impact Factor
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    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 01/2010; 29(28).
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    ABSTRACT: In this work, three compounds having the same organic moiety (N-methyl-5-azahelicenium salts) but different counterions (I-, NO3- and COOCF3-) have been investigated in buffered aqueous solutions and in the presence of DNA to give information on the counterion effects on the binding. In particular, the absorption spectra, fluorescence quantum yields and fluorescence lifetimes in aqueous solution for free organic molecules have been determined by steady-state and time-resolved spectrofluorimetric measurements. The obtained values are compared with those of the chromophores in the presence of increasing concentrations of DNA. The results allow determination of the association constants (K(a)) and the number of base couples per chromophore molecule (n) by means of the McGhee Von Hippel model. The binding parameters are strongly affected by the nature of counterions since the highest K(a) value was determined for the compound having COOCF3-; on the other hand the NO3- derivative is able to interact with the highest number of binding sites. The morphology and structural properties of the DNA-chromophore complexes were investigated by circular dichroism (CD) and atomic force microscopy (AFM). The data revealed that I- and COOCF3- derivatives preferentially form intercalation complexes, while the NO3- salt is able to form intercalation and grove binding complexes at the same time.
    Photochemical and Photobiological Sciences 11/2009; 8(11):1574-82. · 2.92 Impact Factor
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    ABSTRACT: The photophysical properties of three quinolizinium salts (naphto[2,1-b]quinolizinium bromide (Q2), naphto[1,2-b]quinolizinium bromide (Q3), and indolo[2,3-b]quinolizinium tetrafluoroborate (HI)) in fluid media and their interactions with DNA were investigated by steady-state and by nanosecond and femtosecond time-resolved techniques. The main decay pathways of the excited singlet state S(1), fluorescence, intersystem crossing, and internal conversion, were characterized in terms of quantum yields and rate constants. The lowest triplet state of the quinolizinium salts is able to sensitize singlet oxygen in rather high efficiency (phi(Delta) = 0.4 to 0.5 in MeCN). The complexes between quinolizinium salts and DNA formed in the ground state were characterized in terms of lifetimes and decay channels to give more details of the mechanism of photoinduced DNA strand break.
    The Journal of Physical Chemistry A 08/2009; 113(52):14514-20. · 2.77 Impact Factor
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    ABSTRACT: The decay processes of the lowest excited singlet and triplet states of five methylated angelicins (4,6,4′-trimethyl-angelicin, MA, and four methylated thioangelicins, MTA; see Scheme 1) were investigated in live solvents by stationary and pulsed fluorometric and flash photolytic techniques. In particular, the solvent effects on absorption, fluorescence, quantum yields of fluorescence (φF) and triplet formation (φT), lifetimes of fluorescence (τF) and the triplet state (τT) and the quantum yields of singlet oxygen production (φΔ) were investigated. Semiempirical (ZINDO/S-CI) calculations were carried out to obtain information (transition probabilities and nature) on the lowest excited singlet and triplet states. The quantum mechanical calculations and the solvent effect on the photophysical properties showed that the lowest excited singlet state (S1) is a partially allowed π,π* state, while the close-lying S2 state is n,π* in nature. The efficiencies of fluorescence, S1→T1 intersystem crossing (ISC) and S1→ S0 internal conversion (IC) strongly depend on the energy gap between S1, and S2 and are explained in terms of the so-called proximity effect. In fact, for MA in cyclohexane, only the S1→ S0 internal conversion is operative, while in acetonitrile and ethanol, where the n.π* state is shifted to higher energy, the efficiencies of fluorescence and ISC increase significantly. The energy gap between S1 and S2 increases in MTA, where the furanic oxygen is replaced by a sulfur atom. Consequently, the solvent effect on the photophysical parameters of MTA is less marked than for MA; e.g. fluorescence and triplet-triplet absorption are also detectable in the nonpolar cyclohexane. The lowest excited singlet state of molecular oxygen O2(1Dg) was produced efficiently in polar solvents by energy transfer from the T1 state of MA and MTA.
    Photochemistry and Photobiology 01/2008; 68(2):164 - 172. · 2.29 Impact Factor
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    ABSTRACT: This paper describes the results of a study of the photophysical properties of various methyl-angelicins (MA) in solvents of different polarity and proticity. The behavior of their excited singlet and triplet states was investigated by fluorometry and nanosecond laser flash photolysis. On the basis of semiempirical (ZINDO/S-CI) calculations and the solvent effect on the absorption and fluorescence properties, the lowest excited singlet state (S1) is assigned to a partially allowed π, π* state. The close lying S2 state is n,π* in nature. The efficiency of the decay pathways of S1 (fluorescence, intersystem crossing and internal conversion) strongly depends on the energy gap between the S1 and S2 states consistent with the manifestation of “proximity effect.” Thus, MA in cyclohexane decay only through S1→ S0 internal conversion, while in acetonitrile and ethanol, where the n, π* state is located at higher energy, their fluorescence and intersystem crossing increase significantly. The lowest excited triplet states (T1) were characterized in terms of their absorption spectra, decay kinetics, molar absorption coefficients and formation quantum yields. The interaction of T1 MA with molecular oxygen leads to an efficient formation of singlet oxygen, as evidenced by the appearance of characteristic IR phosphorescence centered at 1269 nm.
    Photochemistry and Photobiology 01/2008; 64(1):67 - 74. · 2.29 Impact Factor
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    ABSTRACT: The properties of the lowest excited singlet and triplet state of four halo-angelicins (HA) have been investigated by steady-state and time-resolved spectrometric techniques. The study has been performed in solvents with different polarity and proticity: cyclohexane, dioxane, acetonitrile, ethanol and 2,2,2-trifluoroethanol. Absorption and emission spectra showed that the nature of lowest singlet state is mainly π,π* and the transitions are allowed or partially allowed. Absorption coefficients, fluorescence quantum efficiency and lifetimes are also presented. Flash photolysis investigations have indicated the presence of a unique transient assignable to the lowest triplet state T1. The triplet state has been characterized in terms of absorption spectra, decay kinetics, molar absorption coefficients and formation quantum yields. The racing of both intersystem crossing and fluorescence quantum yields going from a non-polar to a highly polar-protic solvent indicates the presence of a S2 state, n,π* in nature, close lying to the π,π* one. The quantum yields of the singlet decay pathways (fluorescence, intersystem crossing and internal conversion) depends markedly on the energy gap between S1 and S2 states in agreement with the manifestation of the “proximity effect”. In fact in cyclohexane HA decay mainly through S1→S0 internal conversion, while in trifluoroethanol their fluorescence and intersystem crossing increase significantly.Singlet-oxygen quantum yields have been also determined in order to understand the possible application of the investigated drugs in photodynamic therapy. The absence of photochemical pathways allowed the indirect evaluation of the internal conversion decay bringing to the achievement of a complete decay pathways picture.
    Journal of Photochemistry and Photobiology A-chemistry - J PHOTOCHEM PHOTOBIOL A-CHEM. 01/2008; 198(1):98-105.
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    ABSTRACT: ZnAl hydrotalcites containing increasing amounts of 9-anthracenecarboxylate anion (9AC) have been obtained via an anion-exchange procedure. In particular, intercalated and/or surface-exchanged samples were prepared to study the effect of the chromophore packing on their photophysical and photochemical behavior. Surface-exchanged samples were obtained by equilibrating the carbonate form of the ZnAl hydrotalcite with dilute solutions of 9AC. The nitrate form of the ZnAl hydrotalcite was instead chosen for the preparation of intercalation compounds. The maximum loading of 9AC was found to be 44% of the anion-exchange capacity. The obtained nanostructured materials were characterized by chemical and thermal analysis and X-ray powder diffractometry and studied for their photophysical and photochemical properties. The absorption and emission spectra of the materials revealed the formation of 9AC aggregates. The time-resolved fluorescence properties of the hybrid materials were investigated in bulk and under space-resolved conditions. The fluorescence decays appeared to be quite complex and were affected by the microenvironment and the experimental conditions. Generally, a shortening of the main fluorescence decay component was observed with increasing matrix loading, thus suggesting the occurrence of nonradiative processes in competition with fluorescence at high chromophore concentrations. Indeed, the occurrence of an electron-transfer process to water molecules, which led to the formation of 9AC radical, was observed spectrophotometrically in the sample with high 9AC loading. The electron-transfer process was completely reversible under air-equilibrated conditions.
    Langmuir 12/2007; 23(24):12337-43. · 4.38 Impact Factor
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    ABSTRACT: This article describes the results of a coupled photophysical and photobiological study aimed at understanding the phototoxicity mechanism of the antimalarial drugs amodiaquine (AQ), primaquine (PQ) and chloroquine (CQ). Photophysical experiments were carried out in aqueous solutions by steady-state and time-resolved spectrometric techniques to obtain information on the different decay pathways of the excited states of the drugs and on the transient species formed upon laser irradiation. The results showed that all three drugs possess very low fluorescence quantum yields (10(-2)-10(-4)). Laser flash photolysis experiments proved the occurrence of photoionization processes leading to the formation of a radical cation in all three systems. In the case of AQ the lowest triplet state was also detected. Together with the photophysical properties the photobiological properties of the antimalarial drugs were investigated under UV irradiation, on various biological targets through a series of in vitro assays. Phototoxicity on mouse 3T3 fibroblast and human keratinocyte cell lines NCTC-2544 was detected for PQ and CQ but not for AQ. In particular, PQ- and CQ-induced apoptosis was revealed by the externalization of phosphatidylserine. Furthermore, upon UV irradiation, the drugs caused significant variations of the mitochondrial potential (Deltapsi(mt)) measured by flow cytometry. The photodamages produced by the drugs were also evaluated on proteins, lipids and DNA. The combined approaches were useful in understanding the mechanism of phototoxicity induced by these antimalarial drugs.
    Photochemistry and Photobiology 10/2007; 83(6):1415-27. · 2.29 Impact Factor
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    ABSTRACT: This article describes the results of a combined photophysical and photobiological study aimed at understanding the phototoxicity mechanism of the antimalarial drugs quinine (Q), quinacrine (QC) and mefloquine (MQ). Photophysical experiments were carried out in aqueous solutions by stationary and time-resolved fluorimetry and by laser flash pbotolysis to obtain information on the various decay pathways of the excited states of the drugs and on transient species formed on irradiation. The results obtained showed that fluorescence and intersystem crossing account for all the adsorbed quanta for Q and MQ (quantum yield of about 0.1 and 0.9, respectively) and only for 24% in the case of QC, which has a negligible fluorescence quantum yield (0.001). Laser flash photolysis experiments evidenced, for QC and, MQ, the occurrence of photoionization processes leading to the formation of the radical cations of the drugs. The effects of tryptophan and histidine on the excited states and transient species of the three drugs were also investigated. In parallel, the photoactivity of the antimalarial drugs was investigated under UV irradiation on various biological targets through a series of in vitro assays in the presence and in the absence of oxygen. Phototoxicity on 3T3 cultured fibroblasts and lipid photoperoxidation were observed for all the drugs. The photodamage produced by the drugs was also evaluated on proteins by measuring the photosensitized cross-linking of spectrin. The combined approaches were proven to be usefulfor understanding the mechanism of phototoxicity induced by the antimalarial drugs.
    Photochemistry and Photobiology 04/2007; 79(3):248 - 258. · 2.29 Impact Factor
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    ABSTRACT: The interactions and the photosensitizing activity of three antimalarial drugs quinine (Q), mefloquine (MQ) and quinacrine (QC) toward DNA was studied. Evidences obtained by absorption and emission spectroscopy and by linear dichroism measurements indicate that these derivatives bind the macromolecule with a high affinity (binding constants Ka approximately 10(5) M(-1)). The absorption characteristics of the drugs changed markedly by addition of DNA and their fluorescence was quenched with rate constants higher than that of diffusion. The geometry of binding involves predominantly the intercalation into the double helix. The DNA photocleavage properties of antimalarials was investigated using plasmid DNA as a model, at different [drug]/ [DNA] ratios. The results indicate that mainly MQ and Q are able to induce significant photodamage to DNA. In particular the marked effect of the former drug is evidenced after treatment of photosensitized DNA by two base excision repair enzymes, formamydo-pyrimidine glycosilase (Fpg) and Endonuclease III (Endo III). From a mechanistic point of view, experiments carried out in different experimental conditions indicate that these drugs photoinduce DNA damage through singlet oxygen and/or radical cation production. These findings are further supported by the determination of two photoproducts of 2'-deoxyguanosine, which are diagnostic for Type I and Type II pathways, namely 2,2-diamino(2-deoxy-beta-D-erythro-pentofuranosyl)-4-amino-5(2H)-oxazolone and (R,S)4-hydroxy-8-oxo-4,8-dihydro-2'-deoxyguanosine (4-OH-8-oxo-dGuo). Laser flash photolysis experiments carried out in the presence of DNA indicates that the excitation produces mainly the triplet state for Q and the triplet and radical cation for QC. Moreover the singlet and triplet states and radical cations of the drugs are quenched by 2'-deoxyguanosine monophosphate. The absorbances of these transients decrease with increasing DNA concentration.
    Photochemistry and Photobiology 04/2007; 83(3):664-74. · 2.29 Impact Factor
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    ABSTRACT: Photosensitized protein oxidation by drugs, with the consequent modification of their structure is thought to be responsible for the occurrence of phototoxic phenomena such as photoallergy and loss of biological functions. In this paper we have investigated in detail the interaction of four fluoroquinolones namely ciprofloxacin, lomefloxacin, norfloxacin and ofloxacin with two proteins such as Bovine Serum Albumin (BSA) and Ribonuclease A (RNAse A) chosen as models. The interactions between the four drugs and the proteins, were studied by absorption and emission spectroscopy. Photophysical experiments were carried out in aqueous solutions by stationary and time-resolved fluorimetry and by laser flash photolysis, in the absence and in the presence of the proteins to obtain information on the various decay pathways of the excited states of the drugs and on transient species formed upon irradiation. In parallel we have investigated by a series of biochemical assays the photoinduced modifications exerted by the four drugs. The obtained results showed that the four drugs are able to photooxidize proteins with the formation of protein-protein cross-link. This effect was also confirmed in isolated erythrocyte membranes. Furthermore the effect of the fluoroquinolones was also evaluated on isolated aromatic aminoacids. In this context the four drugs are able to photodamage in particular tyrosine and histidine. These results are important in the light of the growing interest for the comprehension of the mechanism of phototoxicity induced by these antibacterial drugs.
    Waldemar Adam ARKIVOC. 01/2007;
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    ABSTRACT: Recent studies on the intercalation of azoic and xanthenic dyes and of donor–acceptor couples into the interlayer region of hydrotalcite-like compounds (HTlc) will be reviewed. In particular, the synthetic strategy followed to optimize the intercalation of chromophores, together with the chemical, photophysical and photochemical characterization of the obtained materials are presented. The use of HTlc containing easily exchangeable counter-ions allowed to introduce in the interlayer region, anionic chromophores with large size and different shape; moreover, materials with tunable optical properties (emission spectra and lifetimes) have been obtained by the accurate control of synthetic procedures. The confinement of chromophores into the interlayer nanometer-space affords the control of the distance between the guest species and hence of their interactions. Confocal microscopy has been used to investigate the distribution of the fluorescent guests into the microcrystals and the host–guest interactions. Furthermore, the preparation and the fluorescence properties of new intercalation compounds formed between HTlc and xylenol orange anions and between 4-phenylazobenzoate and HTlc, in the presence and absence of an electric field, are reported and discussed with the aim to furnish a wider overview of the potentiality of this emerging class of hybrid materials.
    Inorganica Chimica Acta - INORG CHIM ACTA. 01/2007; 360(3):728-740.
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    ABSTRACT: Nanoparticles were prepared in different experimental conditions by a re-precipitation method by use of perylene and polyvinylalcohol as active material and stabilizer, respectively. The excitation and emission spectral properties of dispersions in aqueous solutions of the various samples were recorded together with the fluorescence quantum yields and lifetimes (where detectable). The experimental results are consistent with the formation of excimer-like states, responsible of the emission properties, in the nanoparticles. Confocal fluorescence and atomic force (AFM) microscopies were able to give information on the fluo-rescence properties and size distribution (most probable size of 3 – 5 nm) of the nanoparticles.
    physica status solidi (a) 01/2006; 203(81):1470-1475. · 1.21 Impact Factor
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    ABSTRACT: Intercalation products of Cloisite commercial clay and of Cloisite/polypropylene nanocomposite materials with Rhodamine B dye have been prepared and characterized for chemical composition, X-ray diffraction patterns, thermogravimetric analysis and scanning electron microscopy. They were also investigated by absorption and emission spectroscopies to have information on the dispersion of Cloisite into the polymer. Furthermore, the space-resolved fluorescence properties of powders and solid nanocomposites were investigated by a confocal scanning microscope coupled to a fluorimeter to study the local arrangement of the dye in the solid samples. In particular, the fluorescence images gave information on the three-dimensional morphology and on the distribution of the inorganic matrix within the composite materials; the fluorescence spectra recorded from different positions on the samples were used to characterise the dye located in different sites. These results are interpreted in terms of arrangement and distribution of the dye molecules between the organic and inorganic matrices and nano-dispersion of Cloisite in the polymer.
    Journal of Physics and Chemistry of Solids 01/2006; · 1.53 Impact Factor
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    ABSTRACT: Hydrotalcite is a biocompatible lamellar anionic clay formed by double hydroxide layers with a metal cation coordinating four OH groups. The different layers are held together by anionic hosts that can be replaced by a simple ion-exchange process. The synthetic Mg-Al-hydrotalcite was used to intercalate ferulic acid, a compound that shows antioxidant properties due to its free radical scavenger capacity. Analysis of the intercalated compound showed a good intercalation percentage (35.53%) accompanied by an increase of the interlayer space from 7.8A (chloride form) to 17.1A due to the presence of the ferulate. The intercalation product was stable in water, did not show any significant degradation after UV-irradiation, had a higher capacity of UV absorption in comparison to both the pure ferulic acid and ferulic acid-hydrotalcite chloride physical mixture. The intercalated compound was formulated in a siliconic cream and the ferulate in vitro release profiles determined.
    International Journal of Pharmaceutics 06/2005; 295(1-2):47-55. · 3.99 Impact Factor
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    ABSTRACT: The photophysical and photochemical behaviour of 6,8-dimethyl-2H-furo[2,3-h]chromen-2-one (6,5′-dimethylangelicin, 6,5′-DMA) was studied by steady state and pulsed techniques and by semiempirical calculations. The fluorescence characteristics and the triplet state properties were determined in solvents of different polarity/proticity. The obtained values of fluorescence quantum yields and lifetimes together with the triplet formation quantum yield indicate that the energy gap between the two lowest excited states controls the decay pathways of the singlet. In non-polar and non-protic solvents the internal conversion is almost the sole decay process of the singlet, while in protic solvents the intersystem crossing reaches substantial quantum yields. The effect of ground state concentration on the fluorescence lifetime suggested the occurrence of aggregation while the triplet lifetime was quenched and the rate constant of self-quenching was determined.The 6,5′-DMA photodimerization was investigated in different solvents and in different experimental conditions. Two pyrone-pyrone and one furan–pyrone photodimers of 6,5′-DMA were the main photoproducts detected in the irradiated solution. The effects of the 6,5′-DMA concentration and of oxygen on the amounts of the dimers obtained together with the photophysical behaviour gave indications on the formation mechanism of different dimers.
    Journal of Photochemistry and Photobiology A: Chemistry. 01/2005; 175(1):69-78.
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    ABSTRACT: Two antibacterial fluoroquinolones, levofloxacin and moxifloxacin, were investigated to evaluate their photophysical properties and to explore the mechanism of their phototoxicity. Photophysical experiments were carried out in aqueous solution by stationary and time-resolved fluorimetry, and by laser flash photolysis, to obtain information on the various decay pathways of the excited states of the drugs and on transient species formed upon irradiation. The results obtained show that levofloxacin is able to photosensitize red blood cell lysis in an oxygen-independent way and induce a high decrease in cell viability after UVA irradiation, although to a lesser degree than the racemic mixture ofloxacin. Moxifloxacin, which is an 8-MeO-substituted fluoroquinolone, is less phototoxic than the other compounds. Cellular phototoxicity was inhibited by the addition of superoxide dismutase, catalase, and free radical and hydroxyl radical scavengers (BHA, GSH, mannitol, and DMTU), indicating the involvement of superoxide anion and/or a radical mechanism in their cytotoxicity. A good correlation was observed between lipid peroxidation, protein photodamage, and cellular phototoxicity, indicating that test compounds exert their toxic effects mainly in the cellular membrane. Experiments carried out on pBR322 DNA show that these derivatives do not significantly photocleave DNA directly, but single-strand breaks were evidenced after treatment of photosensitized DNA by two base-excision-repair enzymes, and Endo III.
    Chemistry & Biodiversity 06/2004; 1(5):782-801. · 1.81 Impact Factor
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    ABSTRACT: This article describes the results of a combined photophysical and photobiological study aimed at understanding the phototoxicity mechanism of the antimalarial drugs quinine (Q), quinacrine (QC) and mefloquine (MQ). Photophysical experiments were carried out in aqueous solutions by stationary and time-resolved fluorimetry and by laser flash photolysis to obtain information on the various decay pathways of the excited states of the drugs and on transient species formed on irradiation. The results obtained showed that fluorescence and intersystem crossing account for all the adsorbed quanta for Q and MQ (quantum yield of about 0.1 and 0.9, respectively) and only for 24% in the case of QC, which has a negligible fluorescence quantum yield (0.001). Laser flash photolysis experiments evidenced, for QC and MQ, the occurrence of photoionization processes leading to the formation of the radical cations of the drugs. The effects of tryptophan and histidine on the excited states and transient species of the three drugs were also investigated. In parallel, the photoactivity of the antimalarial drugs was investigated under UV irradiation on various biological targets through a series of in vitro assays in the presence and in the absence of oxygen. Phototoxicity on 3T3 cultured fibroblasts and lipid photoperoxidation were observed for all the drugs. The photodamage produced by the drugs was also evaluated on proteins by measuring the photosensitized cross-linking of spectrin. The combined approaches were proven to be useful for understanding the mechanism of phototoxicity induced by the antimalarial drugs.
    Photochemistry and Photobiology 04/2004; 79(3):248-58. · 2.29 Impact Factor
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    ABSTRACT: The physical and chemical photo-responses of azobenzene were employed to investigate the ‘nanoscopic’ properties of a layered zirconium phosphonate of formula ZrF(O3PCH2)2NHC8H17 (ZrC8, interlayer distance 1.82 nm), a solid belonging to a new family of zirconium diphosphonates with a poorly hindered interlayer region. Two samples were prepared: an intercalation compound containing 0.8 mol of dye per mol of zirconium, having an interlayer distance of 2.82 nm; and a compound in which the azobenzene was adsorbed on the surface of the host. The photobehaviour of the samples was examined by absorption, fluorescence and photochemical techniques and compared with those of the dye in the solid state and in solution. Intercalated or adsorbed azobenzene is able to fluoresce not only from the lowest excited singlet state 1(n,π*) but also from the upper one 1(π,π*), as observed in the solid dye. However, differently from what happens in the pure solid dye, the trans→cis photoisomerization of azo-groups occurred in both intercalated and adsorbed samples upon UV irradiation. The structural changes associated with the photoisomerization process in the interlamellar region induced an irreversible deintercalation of the dye, which was detected as adsorbed on the host surface or present in an amorphous phase. Space-resolved properties of the ZrC8–azobenzene materials were investigated by confocal fluorescence microscopy.
    Journal of Materials Chemistry 01/2004; 14:1656-1662. · 5.97 Impact Factor

Publication Stats

268 Citations
133.27 Total Impact Points

Institutions

  • 1997–2010
    • University of Padova
      • Department of Pediatrics
      Padua, Veneto, Italy
  • 1974–2010
    • Università degli Studi di Perugia
      • Department of Chemistry
      Perugia, Umbria, Italy
  • 2000
    • New University of Lisbon
      • Institute of Chemical and Biological Technology (ITQB)
      Portugal