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This work introduces an innovative new method to transport gold nanoparticles (Au-NPs) toward specific organs using as transporter the M13 filamentous phage. The aim is to improve the radiotherapy efficiency by injecting gold nanoparticles in the tumor tissues in order to increase the effective atomic number and, consequently, to produce higher locally deposited doses. The biocompatible Au-NPs can be bonded to the phage surface for their transport in the biological fluids and tissues. M13 phages can be prepared to arrive in specific tissues and organs depending on their biochemical preparation and functionalization. Evidence about the real attachment of spherical Au-NPs, 10 nm in diameter, to the M13 phages is obtained using different microscopies. Other analyses have been also performed to evaluate the number of gold nanoparticles that can be transported by M13 phages inside the organism. Our results on the study of the spherical Au-NP size distribution, deduced by AFM, EFM, and TEM analyses, have indicated that in average, 2 couples of Au-NPs are attached to each phage. Moreover, the size of the NPs ranges between 10 and 30 nm, demonstrating a little aggregation of the nanoparticles, which remain usefully sized to be vehicled with the blood flux towards specific organs.

A Nd:YAG laser operating at 1064 nm was used to irradiate, at different intensities, graphene oxide foils placed in vacuum and in air. The laser irradiated GO foils were analysed successively by using different techniques such as 2.0 MeV alpha particle Rutherford backscattering spectrometry, X-ray photoemission spectroscopy and SEM-EDX. In particular, in vacuum irradiated graphene oxide samples the oxygen reduction has been observed with increment of the carbon content. In air irradiated GO samples an increase in oxygen has instead been highlighted. Furthermore thermal and chemical effects are induced by the photon irradiation. Results will be presented and discussed.

Room-temperature absorption and reflectivity spectra of MnPSe_3 seleniophosphate crystals have been analyzed from 1.0 to 5.5 eV. A general consistency has been found between the two types of data. From the absorption data an optical energy gap of 2.27 eV was deduced for this compound, in agreement with the literature. A weak and broad absorption band below the fundamental absorption edge was also observed. The reflectivity spectrum exhibits five structures, of which two are located below the fundamental absorption threshold, whereas the others are positioned at higher energies. Spectra have been found to be similar to those reported for the corresponding MnPS_3 thiophosphate, with all the structures beyond the absorption edge shifted toward lower energies. For photon energies greater than absorption edge the MnPSe_3 reflectivity spectrum also shows a similarity to those obtained for the cadmium and mercury seleniophosphates. With this resemblance taken into account, the observed structures have been interpreted in terms of both the so-called transition-metal weakly interacting model and the weak-crystal-field theory. A simplified energy-band diagram, in which the electronic transitions that are responsible for the noted absorption and reflectivity features are clearly indicated, is drawn.

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