Water adsorbed in nanoporous silica glass has been investigated by Raman spectroscopy. The analysis was performed as a function of temperature (from +5 to +75°C), pore diameter (25 and 75Å) and by changing the nature of the substrate (from hydrophilic to hydrophobic) in order to understand the role played on the dynamic peculiarities of water arrangements both by the bare geometrical confinement and the specific interaction with surface. The experimental spectra, collected in the intra-molecular O-H stretching vibrational region, have been decomposed into a sum of sub-bands, representing water molecule arrangements with different types of hydrogen bonding. Hence, we gave a quantitative picture of the temperature and confinement effects on the connectivity pattern.

No abstract

The aim of this study was the investigation of static magnetic field effects on haemoglobin secondary structure and the bioprotective effectiveness of two disaccharides, sucrose and trehalose. Samples of haemoglobin aqueous solutions, in the absence and in the presence of sucrose and trehalose, were exposed to a uniform magnetic field at 200 mT, which is the exposure limit established by the ICNIRP recommendation for occupational exposure. Spectral analysis by FTIR spectroscopy after 3 and 7 h of exposure revealed a decrease in the amide A vibration band for haemoglobin in bi-distilled water solution. Analogue exposures did not produce any appreciable change of amide A for haemoglobin in sucrose and trehalose solutions. Otherwise, no relative increase of [Formula: see text]-sheet contents in amide I and II regions was detected for haemoglobin aqueous solutions, leading us to exclude the hypothesis that static magnetic fields can induce the formation of aggregates in the protein. In addition, a decrease in CH(3) stretching linkages occurred for haemoglobin in bi-distilled water solution after exposure, which was not observed for haemoglobin in sucrose and trehalose aqueous solutions, providing further evidence of a bioprotective compensatory mechanism of such disaccharides.

No abstract

In the present work, we report on a preliminary Fourier Transform Infrared (FT-IR) Absorbance study performed on different kind of rat tissues, such as kidney and heart, exposed to a “non-ionizing” radiation source at low frequency, in the range typical of micro-waves (300 MHz <v< 300 GHz). The data were collected in a wide wavenumber region, from 400 cm−1to 4000 cm−1. The comparison of the absorbance spectra in the case of the normal tissues with the irradiated ones has shown significant differences in the spectral features in accordance with the morphological analysis performed by the optical microscopy.