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A combination of Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) and 2D correlation analysis (2D-COS) was applied here for the first time in order to investigate the temperature-dependent dynamical evolution occurring in a particular type of inclusion complex, based on sulfobutylether-β-cyclodextrin (SBE-β-CD) as hosting agent and Coumestrol (7,12-dihydorxcoumestane, Coum), a poorly-soluble active compound known for its anti-viral and anti-oxidant activity. For this purpose, synchronous and asynchronous 2D spectra were calculated in three different wavenumber regions (960–1320 cm−1, 1580–1760 cm−1 and 2780–3750 cm−1) and over a temperature range between 250 K and 340 K. The resolution enhancement provided by the 2D-COS offers the possibility to extract the sequential order of events tracked by specific functional groups of the system, and allows, at the same time, the overcoming of some of the limits associated with conventional 1D FTIR-ATR analysis. Acquired information could be used, in principle, for the definition of an optimized procedure capable to provide high-performance T-sensitive drug carrier systems for different applications.

This study was aimed at preparing and characterizing solid lipid nanoparticles loading rutin (RT-SLNs) for the treatment of oxidative stress-induced diseases. Phospholipon 80H® as a solid lipid and Polysorbate 80 as surfactant were used for the SLNs preparation, using the solvent emulsification/diffusion method. We obtained spherical RT-SLNs with low sizes, ranging from 40 to 60 nm (hydrodynamic radius) for the SLNs prepared starting from 2% and 5% (w/w) theoretical amount. All prepared formulations showed negative zeta-potential values. RT was efficiently encapsulated within SLNs, obtaining high encapsulation efficiency and drug content percentages, particularly for SLNs prepared with a 5% theoretical amount of RT. In vitro release profiles and analysis of the obtained data applying different kinetic models revealed Fickian diffusion as the main mechanism of RT release from the SLNs. The morphology of RT-SLNs was characterized by scanning electron microscopy (SEM), whereas the interactions between RT and the lipid matrix were investigated by Raman spectroscopy, evidencing spectral modifications of characteristic bands of RT due to the establishment of new interactions. Finally, antioxidant activity assay on human glioblastoma astrocytoma (U373) culture cells showed a dose-dependent activity for RT-SLNs, particularly at the highest assayed dose (50 μM), whereas the free drug showed the lesser activity.

The ability of Captisol® (sulphobutylether-β-cyclodextrin, SBE-β-CD), to form inclusion complexes, both in solution and in the solid state, has been tested in order to improve some unfavorable chemical-physical characteristics, such as poor solubility in water, of a bioflavonoid, Coumestrol (Coum), well known for its anti-oxidant, anti-inflammatory, anti-fungal and anti-viral activity. In pure water, a phase-solubility study was carried out to evaluate the enhancement of the solubility of Coum and, therefore, the occurred complexation with the macrocycle. The stoichiometry and the stability constant of the SBE-β-CD/Coum complex were calculated with the phase solubility method and through the Job's plot. After that, the solid SBE-β-CD/Coum complex was prepared utilizing a kneading method. The spectral changes induced by complexation on characteristic vibrational band of Coum were complementary investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) and Raman spectroscopy, putting into evidence the guest chemical groups involved in the “host-guest” interactions responsible of the formation and stabilization of the complex. Particular attention was paid to the C O and O H stretching vibrations, whose temperature-evolution respectively furnished the enthalpy changes associated to the binding of host and guest in solid phase and to the reorganization of the hydrogen bond scheme upon complexation. From the whole set of results, an inclusion geometry is also proposed.

In the present work, a variety of fragments of frescoes coming from the Villa dei Quintili in Rome (Italy) and dating back to the II century A.D. were subjected to, first of all, an X-ray fluorescence (XRF) analysis by optimizing a portable spectrometer for non-destructive investigation in the field of cultural heritage. The innovative aspect is the ability to obtain coloured maps referring to the distribution and concentration of elements present in the sample. Other than characterization, the aim was to improve the technique for non-invasive and fast in situ analysis. It has been performed, in conjunction with portable Raman analysis, at the ruins of the Villa dei Quintili on samples of different typologies including pottery, statues and frescoes, dating back to the II/III century A.D., different in colour, support and shape. From the results, the identification of the main pigmenting agents is attempted, providing the group of archaeologists in the villa with extremely valuable information for their work too. In particular, by comparing the XRF results for frescoes analysed in the laboratory, taken from the warehouse of the villa, and XRF and Raman data of frescoes analysed in situ, for which the provenance area inside the villa was known, the context of excavation and the manufacture process for some of the former has been hypothesized.

The scientific investigation of the techniques employed by the artist, such as composition of the paints, color palette, and painting style represents a fundamental pre-requisite in order to develop proper conservation and restoration strategies. In this context, the combined use of non-destructive, non-invasive in situ image and chemical analyses was here successfully employed for the investigation of the XVIII century Madonna della Lettera panel painting from the ancient Basilian abbey of Santa Maria di Bordonaro in Messina (Italy). The used techniques were visible, infrared (IR) and false-color infrared (FCIR) photography, X-ray radiography, X-ray fluorescence (XRF) and Raman spectroscopy. The goal was to obtain accurate information on materials and techniques originally used and possible later interventions, with particular regard to the nature of the painting materials. From the results, details of the artwork useful for restoration and conservation procedures were revealed. The identification of most of the artist's palette was also achieved: Prussian blue for blue color, lead white for white, umber for the brown, cinnabar for the red, and carbon black for the black color. The composition of different preparatory substrates was also investigated. The obtained results, other than constituting a crucial step for future restoration works, can be at the same time useful for the dating of the painting, that does not report the date and the artist's signature.

The swelling behaviour of β-cyclodextrin nanosponges, a new class of polymers obtained by reacting β-cyclodextrin with pyromellitic dianhydride, has been here investigated by the analysis of the vibrational dynamics performed by using Fourier-transform infrared spectroscopy in Attenuated Total Reflectance geometry and Raman scattering. The measurements have been carried out at different hydration levels and in the temperature range 250 K–310 K. The decomposition and assignment of the spectral components of the O–H stretching band have been discussed in terms of water molecules engaged in different hydrogen bonding networks, allowing us to recognize three different ‘types’ of water, namely ‘bonded’, ‘intermediate'and ‘free’. By following this approach, a detailed picture of the connectivity pattern of water molecules inside the polymeric matrix is achieved. The analysis of HOH bending vibrational band gives further information perfectly consistent with the results obtained from the analysis of the O–H stretching spectral region. Copyright © 2013 John Wiley & Sons, Ltd.

Cyclodextrin nanosponges (CDNS) are cross-linked polymers with remarkable inclusion/release properties. CDNS show swelling capability and a hydrophilicity/hydrophobicity balance that can be dramatically modified by the type and quantity of cross-linking agents. Here, we focus our attention on samples of beta-cyclodextrin nanosponges (beta-CDNS) obtained by reacting beta-cyclodextrin (beta-CD) with the cross-linking agent carbonyldiimidazole at different beta-CD:cross-linking agent molar ratio. The vibrational properties of CDNS thus synthesized have been investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry and Raman spectroscopy in the dry state at room temperature. The quantitative analysis of the O-H stretching region (3,000-3,800 cm(-1)) allowed us to obtain structural information on the role played by primary and secondary OH groups in the hydrogen bond network of the polymer. Also, the contribution of interstitial and intracavity crystallization water molecules is reported. Solid-state NMR spectroscopy is used to study the molecular mobility of the polymer by measuring the H-1 spin-lattice relaxation time in the rotating frame (T-1 rho). The T-1 rho values obtained for the polymer beta-CDNS are compared with free beta-CD. The observed relaxation parameters point out that the ester formation occurs mainly at the primary OH groups of CDs, also supporting the interpretation of vibrational spectra.

In this work, we present a FT-IR absorbance investigation on prehistoric ceramics with the aim of characterizing the phase transformations that occur during the cooking processes. The measurements were performed on several potteries belonging to the Middle Bronze Age excavated in the Catania hinterland (Sicily, Southern Italy). Based on the macroscopic observation, the samples may be distinguished on coarse and fine ceramics, and the petrographic study showed a strongly heterogeneous structure and composition. The results were compared with the data obtained by means of X-ray diffraction (XRD) and with the microscopic qualitative observations of the birefringence of the groundmass. The whole set of the data showed a firing temperature in the 800–900 °C range. The simultaneous presence in several samples of calcite and clay minerals and of new-formed Ca-silicates should be indicative of a quite primitive technological firing process with strong temperature variation inside the kiln.

The aim of this study was the microscopic and mesoscopic characterisation of archaeological pottery findings addressed to the identification of the manufacturing techniques. The samples under study were “Ionian Cups” sherds, coming from Poira, an archaeological site in eastern Sicily (South-Italy). These cups represent a ceramic typology widely diffused in the Mediterranean Area in archaic age (VI–V century BC). The identification of the production sites of these materials, originally manufactured in Greek-Eastern area and then largely diffused in Magna Graecia, is still an open question. Here, the microscopic structural characterisation was obtained by Fourier Transform Infrared absorption (FT-IR) measurements, which permitted us to determine the mineralogical phases present in the artefacts. Furthermore, Small Angle Neutron Scattering (SANS) measurements permitted the characterisation of the size distribution and surface characteristics of the mesoscopic aggregates formed by the minerals.

The effects of chiral discrimination in inclusion complexes formed by native β-cyclodextrin and its substituted form (namely methyl-β-cyclodextrin) with racemate or pure enantiomers of the non-steroidal anti-inflammatory drug ibuprofen have been investigated in water. Stability constants and complexation efficiency have been determined for these host–guest systems with a 1:1 molar ratio from phase solubility profiles, showing that in aqueous solution, methylated cyclodextrin is a better complex agent than native cyclodextrin, with more enhanced effects for the (R)-enantiomer. These results have been validated using NMR technique. In particular, 1H NMR spectra in D2O show a splitting of the signals for the methyl group and the aromatic protons close to the asymmetric centre of the racemate ibuprofen included in cyclodextrin cavity.

Specific recognition of cell-targeting systems as host-carriers modified with receptor targeting groups, is a major ambition in the application of supramolecular science to medicine and life science. Genistein (Gen), an isoflavone belonging to the class of phytoestrogens, is of great interest because it has been considered as potential remedy for many kinds of disease. In this work, Genistein in aqueous medium and in the presence of an host nanocarrier as amphiphilic cyclodextrin (CyD) modified in the upper rim with oligoethylene hydroxyl groups [(2-oligo(ethyleneoxide)-6-hexylthio)-β-CyD, SC6OH] at 1:1 molar ratio, has been firstly investigated by UV–vis measurements coupled with circular dichroism data, in order to characterize the drug/macrocycle binding affinity through the formation of the complex. Furthermore, FTIR–ATR technique has been used to detect the complex formation in solid phase and to characterize the functional groups responsible of the solid Gen/SC6OH complex stability. The infrared absorbance spectra of the complex, collected in a wide range of wavenumber and around the physiological temperature, have been analysed and compared with the spectra of the pure compounds and their physical mixture. By monitoring the most significant changes in the shape and position of the absorbance bands of the Gen functional groups, we showed that the formation and/or modification of polar bonds play the main role in the interaction of the drug with the amphiphilic CyD. From the results, Gen is shown to be entangled in SC6OH nanoaggregates, establishing hydrogen bonding with the hydrophilic PEG chains.

The inlcusion behaviour of unsubstituted β-cyclodextrin (β-CyD) and (2-hydroxypropyl)-β-cyclodextrin (HP-β-CyD), in solution and solid state was studied with regards to a poorly water-soluble bioflavonoid, coumestrol (Coum), namely 7,12-dihydroxycoumestan, well-known for its anti-oxidant, anti-inflammatory, anti-fungal and anti-viral activities. Phase-solubility measurements were performed to evaluate in solution the complexation of the two cyclodextrins, i.e. β-CyD and HP-β-CyD. The stoichiometry and stability constants of the Coum/β-CyD and Coum/HP-β-CyD complexes were calculated by the phase-solubility method, after which drug–cyclodextrin solid systems were prepared by co-precipitation. In solid phase, the formation of inclusion complexes was confirmed by Fourier transform infrared spectroscopy in attenuated total reflectance (FTIR-ATR) geometry. In particular, complexation mechanisms were explained by the significant differences revealed in the FTIR-ATR spectra of physical mixtures with respect to those of the complexes; the use of deconvolution and curve fitting was determinant.

The effect of beta-cyclodextrin (beta-CyD), (2-hydroxypropyl)-beta-cyclodextrin (HP-beta-CyD) and methyl-beta-cyclodextrin (Me-beta-CyD) complexation on the UV absorption of genistein (Gen) was studied in pure water. A phase solubility study was performed, according to the method reported by Higuchi and Connors, to evaluate the changes of isoflavone in the complexation state and the obtained diagrams suggested that it forms complexes with a stoichiometry of 1:1. Then, the solid complexes of genistein with these macrocycles in 1:1 molar ratio were prepared by the co-precipitation method and characterized by FTIR absorption spectroscopy in ATR geometry. The host-guest interactions have been evidenced by monitoring, in the FTIR-ATR spectra, the changes in some guest molecule bands relative to those observed in the spectra of the 1:1 physical mixtures and complexes. In particular, for the high-frequency O-H stretching band, a quantitative vibrational assignment of the observed sub-bands has been made. From the results, the inclusion phenomena have been discussed.

In order to elucidate the effects of the nature of the cross-linker, of the hydration level and of the hydrophobic/ hydrophilic balance on the macro- and microscopic properties of a paradigmatic model of polysaccharide hydrogel, an integrated approach based on the combined use of low-frequency Raman scattering and FTIR-ATR absorption has been developed. The proposed methodology aims to explore the stability range of the liquid and gel phase diagram of the system. This approach was applied to cyclodextrin based nanosponges (CDNS), prepared by polymerization of α-, β-, and γ-cylcodextrins (CDNS) with an activated derivative of ethylenediamine tetra acetic acid. It revealed successful, on one side, for a comparative analysis of the elasticity, as mesoscopic parameter, of the dry polymeric network, measured by Raman spectroscopy in the low frequency (0 ÷ 150 cm–1) range, and, on the other side, for the investigation of the water holding capacity, as macroscopic parameter, through the analysis of the vibrational dynamics of water molecules in the swollen polymers, monitored by FTIR-ATR spectroscopy in two selected wavenumber regions, i.e. 2800 ÷ 3800 cm–1 and 1500 ÷ 1800 cm–1, where the O-H stretching and H-O-H bending vibrations respectively occur. As main result, the same evolution as a function of the molar ratio n, has been observed for the elasticity on mesoscopic scale, as described by the Boson Peak (ωBP) and the swelling ability on macroscopic scale, expressed by the mass ratio m describing the gel-to-sol transition in these systems. From the results, the way for a rational development of stimuli-responsive systems with specific performances, by modulating the stability range of the liquid suspension and gel phases properly changing the molar ratio n during the synthesis, is opened.

A detailed experimental and theoretical vibrational analysis of hydrogels of β-cyclodextrin nanosponges (β-CDNS), obtained by polymerization of β-cyclodextrin (β-CD) with the cross-linking agent ethylenediaminetetraacetic acid (EDTA), is reported here. Thorough structural characterization is achieved by exploiting the complementary selection rules of FTIR-ATR and Raman spectroscopies and by supporting the spectral assignments by DFT calculations of the spectral profiles. The combined analysis of the FTIR-ATR spectra of the polymers hydrated with H2O and D2O allowed us to isolate the HOH bending of water molecules not involved in symmetrical, tetrahedral environments. The analysis of the HOH bending mode was carried out as a function of temperature, showing the existence of a supercooled state of the water molecules. The highest level of cooperativity of the hydrogen bond scheme was reached at a value of the β-CD/EDTA molar ratio n = 6. Finally, the connectivity pattern of "uncoupled" water molecules bound to the nanosponge backbone was found to be weakened by increasing T. The temperature above which the population of non-tetracoordinated water molecules becomes predominant turned out to be independent of the parameter n.

FTIR–ATR spectroscopy has been applied to follow the evolution of intramolecular HOH bending vibrational mode of water in fully hydrated Na-A and various Mg-exchanged A zeolites. The measurements have been performed as a function of temperature and for different percentages of induced ion-exchange. The observed changes have been justified by taking into account the population of water molecules that do not lie in a symmetric tetrahedral environment and the force constants associated to the mode. The data, compared with previous FTIR–ATR O–H stretching spectra for the same samples, give new information to confirm, in the whole explored T-range, the “structure-maker” role played by zeolitic surface on chemisorbed water. It appears systematically enhanced by increasing the percentage of induced ion-exchange.

In the present work, we report a polarized Raman study versus temperature of the complex O–H stretching vibrational band (3800–3000 cm −1 ) performed in a glass forming liquid, namely propylene-glycol (PG), with chemical formula given by H[OCH(CH 3 )CH 2 ]OH. The spectra were collected in bulk and confined state within a sol–gel controlled porous glass having highly interconnected 25 A diameter pores and characterized by a huge number of silanol groups (Si–OH), able to interact with PG molecules via hydrogen bond. The goal was to investigate how the hydrophilic nature of the surface influenced the molecular mobility of this hydrogen-bonded system, by monitoring intra- and inter-molecular host–host and host–guest interactions. The analysed O–H spectral region was decomposed into Gaussian symmetrical profiles, each of them associated to a well-defined aggregate, triggered by the presence of H-bond. Passing from the bulk state to the confined one, a clear change of the dynamical properties has been revealed and related to the interactions with the surface. The observed results were discussed on the basis of current models for associated liquids.

The modification, compared to the bulk state, of the dynamics of liquids in confined geometry has attracted considerable interest in scientific research, also because of the close connection with many relevant technological problems, such as the building of optical switches, membrane separation, catalysis and tertiary oil recovery. We report the preliminary results of an Incoherent Quasi Elastic Neutron Scattering (IQENS) investigation on propylene glycol (PG: H[OCH(CH 3 )CH 2 ]OH), a low molecular weight polymer, both in the bulk and in the confined state, in order to show the different dynamical behaviour of this system as a consequence of the presence of an interface. In particular PG was confined in 26 A pores of a porous sol–gel glass with unmodified and modified inner surface, trying to distinguish the different role played by hydrophobic and hydrophilic confinement on its diffusive motion. The data have been interpreted in the framework of the well known Volino–Dianoux model for confined diffusion, and compared with the most recent literature in this field.

The spectral substructure of the O–H stretching mode of water confined in Mg50-A zeolites is demonstrated, in full hydration conditions and in the temperature range 20–80°C, using Fourier transform Infrared (FT-IR) spectroscopy. Band shapes have been fitted to individual components, according to the actual theories for associated liquids, and three major constituent peaks were derived, at 3230 cm−1 (ω1), 3460 cm−1 (ω2), and 3600 cm−1 (ω3). They have been related, respectively, to an ice-like molecular environment and other hydrogen-bonding configurations. A detailed quantitative analysis of their centre frequencies and relative intensities, traced over the full temperature range investigated, has led to the conclusion that these subbands show direct evidence, under confinement, of bifurcated hydrogen bonds (BHB) among three water molecules as a main feature of the structure of liquid water. The most interesting result comes from the observation, at all temperatures, of the tetrahedral connectivity typical...

The aim of the present work is the characterization of ceramics artefacts coming from Locri Epizephiri, in order to understand the area of production and the baking temperatures. The macroscopic investigation, performed from an archaeological and chronological point of view, permitted the classification of the studied samples into two different groups: the former was constituted of amphorae fragments used for transport, characterized by a mixture of medium-fine grain, and the latter was constituted of tiles fragments with a mixture of coarse grain. All the samples date back to a period between the V and the IV century bc and present similar mineralogical–compositional characteristics. The ceramic samples were analyzed by X-ray diffraction (XRD), X-ray fluorescence and Fourier transform infrared (FT-IR) spectroscopy. XRD spectroscopy allowed us to identify the present crystalline substances. In particular, both in the amphorae and in the tiles, the main mineral is quartz. Furthermore, larger quantities of calcite, hematite and illite are present in the amphorae rather than in the tiles, while a larger amount of K-feldspar is present in the tiles rather than in the amphorae, finally gehlenite is definitively absent in the tiles. The FT-IR investigation was performed both at low and high frequencies. From all the obtained results it was possible to conclude that the provenance area of the ceramics was the Calabro–Peloritano one. The compositional variations could be attributed to the presence of the different workshops in the same zone and to the existence of several quarries of clay materials.

In this paper we report the results of a study of low-frequency vibrational dynamics and electron-vibration coupling in water in the bulk and confined state, at different hydration percentages. The simultaneous use of both Raman spectroscopy and time-of-flight inelastic neutron scattering allowed us to determine the respective vibrational densities of states (VDOSs), g R eff(ω) and g N(ω). Both the VDOSs show clear evidence of surface-induced vibrational modes, due to the local order distortion with respect to the bulk state.

In the present study, an innovative methodological approach has been proposed in order to characterize meteoritic samples without removing or causing damage to any part of them. In particular, Raman and X-ray fluorescence (XRF) measurements have been preliminarily performed, using portable instruments, in order to obtain qualitative and semi-quantitative compositional information, respectively. These analyses have been followed and supported by time of flight neutron diffraction (TOF-ND) experiments, which allowed us to perform quantitative mineralogical phase analysis. Such a methodological approach was tested on four meteoritic samples, of different types and sizes, coming from several different regions of the Solar System (e.g., the Moon, Mars and asteroids). The validity and strength of the results obtained using these techniques are discussed and compared with results available in the literature.

The phase transition from gel to liquid suspension in cyclodextrin (CD)-based hydrogels is in depth monitored by using Fourier transform infrared spectroscopy in attenuated total reflectance geometry. Cyclodextrin nanosponges (CDNS) synthesized by polymerization of CD with the cross-linking agent ethylenediaminetetraacetic dianhydride at different cross-linking agent/CD molar ratios have been left to evolve from gel phase into liquid suspension upon gradual increase of the hydration level. Measurements of the changes occurring in the vibrational dynamics of the system during this transition provide direct evidence of the gel-sol progress of the CNDS hydrogel, by accounting for the connectivity pattern of water molecules concurring to the gelation process. The experimental results clearly indicate that the increase of the hydration level is accompanied by the corresponding increase of the population of H2O molecules engaged in high-connectivity hydrogen-bond networks. The water tetrahedral arrangement is thus dominant above a characteristic cross-over hydration level, experimentally determined for all the investigated samples. The observation of this characteristic cross-over point for the CDNS hydrogel and its correlation with other parameters of the system (e.g. the absorption ability of CDNS and elasticity of the polymer matrix) is, once again, modulated by the cross-linking agent/CD molar ratio. The latter seems indeed to play a key role in defining the nano- and microscopic properties of nanosponge hydrogels.

In this work we report a preliminary study of Fourier transform infrared spectroscopy on normal and neoplastic human skin samples suffering from two kinds of cancer, namely epithelioma and basalioma. The analyzed skin samples have been drawn from different parts of the human body, after biopsies. By performing a complex band deconvolution due to the complexity of the tissue composition, the analysis within the considered frequency region (900–4000 cm−1) of the collected IR spectra, allowed us, first of all, to characterize the presence of the pathologies and to show clear different spectral features passing from the normal tissue to the malignant one in particular within the region (1500–2000 cm−1) typical of the lipid bands.

In the present work IR measurements as a function of temperature, performed, in the (2500−3700) cm-1 region, on ethylene glycol (EG) and its homologous systems, namely ethylene glycol monomethyl ether (EGmE) and ethylene glycol dimethyl ether (EGdE), are presented and discussed. The goal is to analyze the evolution of the O−H stretching fundamental band in a wide range of temperature for systems having identical chemical structure except for the number of hydroxyl end groups, clarifying in this way the processes characterizing the vibrational dynamics of these H-bonded liquids. In particular, the O−H stretching band shape, through a quantitative study performed with FT-IR in the attenuated total reflectance geometry, has been connected to the different transient local environments of hydrogen-bonded molecular groups, and the role played by inter- and intramolecular interactions discussed within the framework of current theories for associated liquids. In addition, temperature-induced isosbestic points obs...

Quasi-elastic light scattering (QELS) was performed in dilute water in oil microemulsion stabilized by AOT surfactant. The water-soluble polyethylene oxide (PEO) with low molecular weight (8000) added to the microemulsion seems to be confined within the aqueous microphase, since PEO is insoluble in oil (n-heptane). The measurements by QELS of diffusion coefficient, at dilute concentrations, allow determination of the size of the droplets. The phase diagram of the microemulsion undergoes remarkable changes on addition of the polymer. The results show that at fixed R ( water surfactant ratio) the droplets decrease their size as the concentration of polymer increases. This occurrence can be related to the change of interface interaction due to the addition of polymer. Moreover, the hydrodynamic radius, near the critical composition, shows critical behaviour, as a function of the reduced temperature, which seems not to be affected by the polymer addition.

Raman scattering spectra of polymeric aqueous solutions of poly(ethylene glycol) vs. concentration and temperature are presented. We show that the shape of the OH band can be reproduced by a suitable superposition of the spectra of bulk and hydration water. The relative amount of the two contributions changes with concentration and temperature, furnishing information on the number of water molecules bonded to the polymer chain. The results show that, when water concentration increases, water molecules saturate the two lone pairs of each oxygen atom of the polymer in agreement with previous adiabatic compressibility and Incoherent Quasi Elastic Neutron Scattering measurements.

An integrated experimental-numerical approach, based on vibrational spectroscopy techniques and quantum chemical computation methods, has been here implemented and tested on a new class of cyclodextrin-based cross-linked polymers, namely, cyclodextrins nanosponges. By the simultaneous quantitative analysis of FTIR-ATR and Raman spectra in the frequency domains between 1650-1800 and 3000-3700 cm(-1), we individuated reliable physical descriptors directly connected to the cross-linking degree of the polymeric matrices. The comparison between the experimental data and the results of the quantum chemical simulations provided structural information on the involvement of the cyclodextrin chemical groups during the polymerization process. This proposed experimental numerical approach appears to be of general application for the investigation of amorphous polymeric matrices of interest for technological application, for which the use of other experimental techniques is seriously hampered by the low or absent level of crystallinity.

The present work reports a detailed investigation on the speciation of iron in the pigments of decorated pottery fragments of cultural heritage relevance. The fragments come from the Gioiosa Guardia archaeological site in the area of the `Strait of Messina' (Sicily, Southern Italy), and date back to VI-V century BC. The purpose of this study is to characterize the main pigmenting agents responsible for the dark-red coloration of the specimens using non-destructive analytical techniques such as synchrotron radiation X-ray absorption spectroscopy (SR-XAS), a well established technique for cultural heritage and environmental subjects. Absorption spectra were collected at the Fe K-edge on the Italian beamline for absorption and diffraction (BM8-GILDA) at the European Synchrotron Radiation Facility in Grenoble (France). In order to determine the speciation of Fe in the samples, principal component analysis and least-squares fitting procedures were applied to the near-edge part of the absorption spectra (XANES). Details on the local structure around the Fe sites were obtained by analyzing the extended part of the spectra (EXAFS). Furthermore, an accurate determination of the average Fe oxidation state was carried out through analysis of the pre-edge peaks of the absorption spectra. Samples resulted composed of an admixture of Fe(2)O(3) (hematite or maghemite) and magnetite (Fe(3)O(4)), occurring in different relative abundance in the dark- and light-colored areas of the specimens. The results obtained are complementary to information previously obtained by means of instrumental neutron activation analysis, Fourier transform infrared absorbance and time-of-flight neutron diffraction.

Measurements performed by means of Small Angle Neutron Scattering (SANS), Incoherent Quasi Elastic Neutron Scattering (IQENS) and Fourier Transform Infrared (FTIR) techniques on reversed water-in-oil micelles are presented and analysed. This ternary system, constituted by water/surfactant Me+n(AOT)n/oil forms droplets whose shapes and sizes have been determined by SANS. Moreover a strong confinement effect for the H2O molecules, whose dynamical properties reflect themselves on the O-H stretching band (FTIR) and on the low frequency diffusive motions (IQENS), is revealed.

Polarized and depolarized Raman data in mixed isomeric alcohols n-Pentanol and 2-Methyl-2-Butanol are presented. The spectra, obtained as a function of temperature and concentration, have been performed in the intramolecular O—H stretching region. The analysis of the spectral features of the deconvoluted bands, center frequency, percentage intensity and halfwidth, performed in the frame of a previous investigation on the pure components, shows that the aggregative processes, present in these H-bonded liquids, reflect themselves also on this spectral region furnishing evidence that, as evidenciated by other techniques, in the 2M-2BuOH rich region, the formation of hetero-structures, determining a strengthened respect to the more “fragile” pure tertiary alcohol, is present.

A non-invasive time-of-flight neutron diffraction (TOF-ND) analysis has been performed on archaeological pottery fragments from the excavation sites in the “Strait of Messina” area (Sicily, Southern Italy). The revealed quantitative information on the mineralogical composition have been compared, in the case of two samples representative of coarse and fine grained pottery, with the weight fractions of the crystalline phases as obtained from X-ray diffraction on powders (XRPD), for different amounts of extracted powder. From the results, the consistency of these micro-destructive and non-invasive approaches has been checked. This research may contribute to better define the most efficient sampling and analytical method for the determination of mineralogical composition on ceramics different in structure and composition.

Solid inclusion complexes of the amino acid ( d , l )-serine and ( l )-serine with β-cyclodextrin (β-CD) have been investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR), in order to put into evidence the effects of chiral properties on the complexation process. The spectral changes induced by complexation in the vibrational spectra of serine have been monitored in the 600–4000 cm−1 range, recognizing the functional groups taking part in the “host–guest” interactions. Again, the quantitative analysis, vs. T, of the C O stretching vibration, by means of a best-fit procedure, furnished the enthalpy changes associated to the binding of serine with β-CD in solid phase. The most stable inclusion complex turned out to be the one formed by ( l )-serine, and then ( d , l )-serine.

We report on a non-destructive study of Sicilian ceramic fragments of cultural heritage interest, classified as "proto-majolica" pottery and dating back to the twelfth to thirteen centuries AD. The analytical approach used is based on the employment of two totally non-invasive spectroscopic techniques: X-ray fluorescence (XRF), using a portable energy-dispersive XRF analyser, and X-ray absorption spectroscopy, using synchrotron radiation as a probe (SR-XAS). XRF measurements allowed us to collect elemental and spatially resolved information on major and minor constituents of the decorated coating of archaeological pottery fragments, so providing preliminary results on the main components characterizing the surface. In particular, we assigned to Fe and Mn the role of key elements of the colouring agent. With the aim of obtaining more detailed information, we performed SR-XAS measurements at the Fe and Mn K-edges at the Italian BM08 beamline at the European Synchrotron Radiation Facility (Grenoble, France). The experimental data were analysed by applying principal component analysis and least-squares fitting to the near-edge part of the spectra (X-ray absorption near-edge structure) to determine the samples' speciation. From the overall results, umber, a class of brownish pigments characterized by a mixture of hydrated iron and manganese oxides, has been ascribed as a pigmenting agent.

Solid inclusion complex of the non-steroidal anti-inflammatory drug Ibuprofen (IBP, (2-[4-(2-methylpropyl)phenyl]-propanoic acid) with (2,6-dimethyl)-β-cyclodextrin (diME-β-CD) has been investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR spectroscopy) and numerical simulation. The complexation-induced changes in the FTIR-ATR spectrum of IBP have been interpreted by comparison with the theoretical vibrational wavenumbers and IR intensities of dimeric structures of IBP, derived from symmetric hydrogen bonding of the two carboxylic groups, computed by using Density Functional Theory (DFT) calculations. From temperature-dependent studies, the enthalpy change Δ H associated with the binding of IBP with diME-β-CD for 1:1 stoichiometry, in solid phase, has been estimated.

Renaissance blue decorated pottery fragments from the archaeological site of Caltagirone (Sicily, Italy) were analysed by scanning electron microscopy – energy dispersive X-ray spectrometry (SEM/EDS). The samples were dated back to 16th century AD on the basis of archaeological observations. The micro-chemical analyses were performed on the ceramic body and the surface decorated layer of the samples. Particularly, the investigation was addressed the characterization of the coating blue decorations. The obtained results allowed us to clearly identify smalt as pigment. Also the presence of arsenic (As) was revealed and the Co/As ratio values were calculated and related to the different process used for the pigment preparation. Further spectroscopic analyses, performed through X-ray absorbance spectroscopy (XAS), carried out at the Co K-edge, confirmed the micro-analytical results and permitted us to identify the oxidation form and the local environment of cobalt atoms.

By pulsed field gradient nuclear magnetic resonance measurements, we investigated the translational diffusion of water confined in the 200 A diameter pores of a sol-gel silica glass. The experiments, performed as a function of the hydration level, showed an enhancement of the self-diffusion coefficient when the water content corresponds to one or fewer monolayers. An explanation for this occurrence has been given in terms of a two-phase process involving a fast molecular exchange between the liquid and the vapor phase. Moreover, in partially filled pores, the surface water diffusion coefficient was measured, and was 4 times lower than the diffusion of liquid confined water in saturated spaces.

In this paper, an incoherent quasi-elastic neutron scattering (IQENS) study of the single-particle dynamics of water in fully hydrated Na-A and Mg50-A zeolites at T = 293 K and T = 333 K is presented. In order to probe different time scales, measurements were made at two resolutions, ∼8 µeV and ∼28 µeV. The high-resolution data allowed us to investigate the slower dynamics, which is mainly translational. The low-resolution spectra were used to probe the faster dynamics and distinguish between diffusional and rotational motion. We found that the partial exchange of Na+ with Mg2+ induces: (a) an increase of the available volume for diffusion; (b) a decrease of the fraction of water molecules taking part in the observed jump diffusion process; and (c) a shortening of the residence time.

In order to explore the influence of cation substitution on the vibrational dynamics of water molecules in zeolites, the evolution of structural properties of the O-H stretching band of water in fully hydrated Na-A and Mg-exchanged A zeolites has been studied, for different percentages of induced ion exchange, by Fourier transform infrared attenuated total reflection spectroscopy as a function of temperature. The differences revealed in the O-H stretching band shapes have been accounted by fitting the spectra as a sum of four components, corresponding to water molecules exhibiting different types of hydrogen bonding. The dependencies of the relative intensities, peak wave numbers, and bandwidths of the resolved components on temperature and Mg2+ content have been discussed. Evidence of the "structure-maker" role played by a zeolitic surface on physisorbed water, systematically enhanced by increasing the percentage of induced ion exchange, is given in the whole explored temperature range.

Raman scattering and Fourier-transform infrared (FT-IR) absorption results on confined water are presented. The aim is to characterize different porous materials, studying the vibrational properties of water inserted in their porous structure, and determining the relationship between these two aspects. Confinement has been realized by using a sol–gel silica glass, GelSil, with 26 A diameter pores of huge hydrophilic inner surface, and NaA type zeolites, with 10 A diameter pores in which 27 H2O molecules can be located. The O–H stretching spectral range (2800–3800 cm−1), as a function of temperature and for different water contents, has been explored. From a comparison of the data in these two cases, we put into evidence the structure breaker role of GelSil, as revealed by the slowing down of the collective contribution to the polarized O–H stretching band, indicating that the tetrabonded H2O network is destroyed. On the other side, NaA zeolites will be proofed to play a structure breaker effect on physisorbed water, since the contribution to the O–H stretching band linked to the tetrahedral ice-like arrangement is present even at the lowest hydration conditions.

In the present work we characterized samples of plasters and pictorial layers taken from a fresco in the Acireale Cathedral. The fresco represents the Coronation of Saint Venera, patron saint of this Ionian town. By performing a detailed spectroscopic analysis of the plaster preparation layer by Fourier-transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD), and of the painting layer by FTIR and confocal Raman microspectroscopy, scanning electron microscopy+energy dispersive x-ray spectroscopy, and XRD, we were able to identify the pigments and the binders present. In particular, Raman investigation was crucial to the characterization of the pigments thanks to the high resolution of the confocal apparatus used. It is worth stressing that the simultaneous use of complementary techniques was able to provide more complete information for the conservation of the artifact we studied. (C) 2005 American Institute of Physics.

The aim of the present work is the characterization of decorated pottery samples from Caltagirone (Sicily, Italy), a renowned production centre of this kind of artwork. These fragments were found during archaeological excavations and were attributed to historical periods extremely far in time from each other (from XVIII century b.C. to XVI a.C.). Therefore, we expect that the manufacture techniques result rather different over so long time. The measurements, performed by Fourier Transform-InfraRed (FT-IR) absorbance and micro-Raman scattering, allowed us a non-destructive study of so precious artefacts. Some pigments were identified, various elements of ceramic paste and glazed layer were characterized.

In the present work, we report a spectroscopic analysis of water confined in a powdered zeolite, Na A type, which is able to entrap 27 H2O molecules, by Fourier transform infrared absorption, performed in the OH stretching region, 3000–3800 cm−1. The investigation was carried out as a function of temperature and at different hydration levels. The spectroscopic results were interpreted in the framework of actual theories for associated liquids and on the basis of previously measurements performed in water confined in a different environment, a controlled silica glass (GelSil), by Raman scattering, always in the OH stretching region. The comparison between these two distinct cases of confinement condition unambiguously showed the role of structure maker played by the zeolite for confined water as opposed to the structure breaker character observed in the case of the GelSil matrix.

In this paper, we go deeply into an analysis performed, as a function of T, by means of incoherent inelastic neutron scattering (IINS), of vibrational dynamics of liquid ethylene glycol (EG: HO–CH2CH2–OH) in the bulk state and confined into 26 A interconnected cylindrical pores of a sol-gel porous glass. IINS spectra revealed, as far as the vibrational density of states, Z(ω) is concerned, a different trend in temperature passing from bulk to confined samples. In particular, we observed a thermal stabilization of the disordered longitudinal acoustic mode as a consequence of the interaction between the hydroxyl groups (OH) of the EG molecules and the active silanol groups (Si–OH) on the surface of the porous glass.

In the present work we report a Fourier Transform Infrared (FT-IR) analysis performed on rat encephalon samples in the CHOH vibrational stretching region (2400–3800) cm−1, in order to reveal the presence of a very diffuse commercial benzodiazepine: VALIUM®. The comparison between the spectral features of normal brain and the ones of samples with administrated substance has unambiguously showed that the CH stretching region seems not to suffer from any change for the pharmacological treatment, instead the OH band is strongly modified probably due to the presence of a new spectral contribution characteristic of diazepam molecule.

The understanding of new phenomena arising in confined condensed matter is important for the physics of interfaces and finite systems. This has stimulated intensive research on solids, liquid crystals and liquids confined in different geometries. Experimental techniques and theoretical approaches have shown that a liquid confined to a region that approaches molecular dimension exhibits dynamic and thermodynamic properties strongly changed relatively to the bulk with increasing geometrical confinement. This was interpreted by geometric as well as absorption effects: the first ones are related to the tortuosity of the interconnected channel for diffusion, the second ones take into account the degree of adsorption of molecules on the active inner surface sites. We present a detailed study of the reorientational, vibrational and diffusional dynamics of ethylene glycol (EG: OH–CH2CH2OH), ethylene glycol monomethyl ether (EGmE: CH3–OCH2CH2OH) and ethylene glycol dimethyl ether (EGdE: CH3–OCH2CH2OCH3), in the bulk state and confined in a matrix of sol–gel porous glass with 26 A interconnected cylindrical pores. This investigation has been performed by means of Rayleigh wing (as far as reorientational dynamics is concerned), Raman (as far as vibrational dynamics is concerned) and Incoherent Quasi Elastic Neutron Scattering (as far as diffusional dynamics is concerned). The clear influence of the confinement on the mobility of the studied liquids, with a dramatic frozen-in effect with respect to the bulk state, is evidenced.

A quantitative analysis of hepatotoxic effects on rat liver, caused by a single administration of carbon tetrachloride (CCl4), and of sequential hepatic regeneration has been performed by the application of biochemical analysis, light microscopy, and Fourier transform infrared (FT-IR) absorption spectroscopy. The joined techniques have allowed to mark the biochemical, structural and dynamical properties (these appear in the O–H vibrational stretching region) of rat liver samples by monitoring the changes versus the time course of injuries. The morphological observations have shown a dramatic increasing of degenerated cellular elements with fatty infiltrations just after 24 h and an initial regeneration already present at 72 h from the CCl4 treatment. As FT-IR measurements are concerned, a vibrational assignment has been made for the observed sub-bands in the analyzed wave number range, by comparing the normal liver spectrum with those in the case of CCl4 administration. In particular, the analysis in the O–H stretching region (3000–3800 cm−1) of intoxicated samples has shown clear changes interpreted on the basis of the structural and biochemical analysis made on the same samples.

We present a detailed Raman scattering study performed in liquid water confined in a porous sol-gel glass having 25 A diameter pores. The measurements were carried out in the OH vibrational stretching region, ranging from 2700 cm-1 to 3700 cm-1 . By comparing the bulk water with the confined one, strong modification of the vibrational dynamics of adsorbed water on the inner surface of the glass matrix becomes clear. Furthermore a preliminary analysis of incoherent quasi-elastic neutron scattering data (IQENS) in confined water reveals a strong confinement effect on the water molecules by the host glass that reflects, consequentially, a hindered diffusional dynamics. The experimental results were interpreted following the well known Volino-Dianoux model.

We employed infrared (IR) absorption and Raman scattering to investigate the vibrational dynamics of ethylene glycol (EG) and its homologous systems, EG monomethylether and EG dimethylether, in bulk and confined into 25 A pores of a sol-gel porous glass. The measurements, performed in the O–H stretching region at room temperature, show the main role played by the H-bond in the structural environments of these liquids, discussed on the basis of current theories for associated systems. The goal is to study the intramolecular H-bond imposed band and to assign the various sub-bands in terms of the different aggregates present, clarifying the dynamical response of these associated systems in this very interesting region. Experimental data in the bulk state compared with those in the confined one give a clear indication of the influence of chemical and physical traps present in the glass matrix.