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This work is aimed at the development of innovative, easy and cheap methods for the stabilization, inertization and valorisation of the organic fraction of municipal solid waste (OFMSW). For the first time, two original processes for transforming the organic waste into an inert, odorless and sanitized material were here proposed. The first one, called dual step, starts with grinding of the OFMSW, by means of an industrial shredder. After being finely ground, the organic waste was exposed to a sterilization process by means of UV/ozone radiations or thermal treatment (stabilization phase) in order to obtain a complete removal of the OFMSW&rsquo, s bacterial activity. By means of several microbiological analyses, the best sterilization method was chosen. The incorporation in a thermosetting matrix was, then, carried out through mixing the sterilized and finely ground organic waste into a water soluble urea formaldehyde (UF) based resin, with a formaldehyde content less than 1% wt, followed by a thermal treatment for UF-resin crosslinking (inertization phase). An alternative cheaper and easier process, called one step, was also proposed and investigated, by combining the sterilization with the curing thermal process (at higher temperature) of the thermosetting matrix. The preliminary experimental results reported in this paper suggest that both the proposed methods could be considered suitable for the production of high valorized innovative OFMSW-derived panels or bricks that could find application in several fields, such as building or construction materials. Finally, a brief description of the prototype machinery, properly designed for implementing OFMSW stabilization and valorization processes, is reported.

This work is aimed at the development of innovative, easy and cheap methods for the stabilization, inertization and valorisation of the organic fraction of municipal solid waste (OFMSW). For the first time, two original processes for transforming the organic waste into an inert, odorless and sanitized material were here proposed. The first one, called dual step, starts with grinding of the OFMSW, by means of an industrial shredder. After being finely ground, the organic waste was exposed to a sterilization process by means of UV/ozone radiations or thermal treatment (stabilization phase) in order to obtain a complete removal of the OFMSW’s bacterial activity. By means of several microbiological analyses, the best sterilization method was chosen. The incorporation in a thermosetting matrix was, then, carried out through mixing the sterilized and finely ground organic waste into a water soluble urea formaldehyde (UF) based resin, with a formaldehyde content less than 1% wt, followed by a thermal treatment for UF-resin crosslinking (inertization phase). An alternative cheaper and easier process, called one step, was also proposed and investigated, by combining the sterilization with the curing thermal process (at higher temperature) of the thermosetting matrix. The preliminary experimental results reported in this paper suggest that both the proposed methods could be considered suitable for the production of high valorized innovative OFMSW-derived panels or bricks, that could find application in several fields, such as building or constructions materials. Finally a brief description of the prototype machinery is reported properly designed for implementing OFMSW stabilization and valorisation processes developed in this research work.

Skin injuries represent a health problem with consequences in terms of morbidity, disability and life quality. Numerous strategies have been developed for the treatment of wounds, including skin substitutes, biomembranes, scaffolds, and smart dressings. The excellent properties of fibroin can be exploited for the development of advanced wound dressing biomaterials, aiming at promoting the wound healing process. In this work, silk fibroin films modified through the addition of glucose were developed to enhance flexibility of medical device without affecting the biocompatibility, to promote wound healing and to improve the patient well-being. The glucose/fibroin blend was characterized through Fourier transform infrared spectroscopy and differential scanning calorimetry to analyze the protein structure. Absorption capacity, mechanical properties, wettability and bacterial biofilm formation on silk fibroin films were also analyzed to study the effect of the addition of a plasticizer on the properties of the wound dressing. The stability of the films was analyzed through in vitro biodegradability tests. The biocompatibility and regenerative properties were demonstrated through appropriate cellular assays. The results demonstrated that the addition of glucose induced crystallization and provided good flexibility and absorption capacity of silk fibroin films. Glucose modified silk fibroin films were biocompatible and had a positive effect in promoting the wound closure. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 7-18, 2019.

Silver nanophases are routinely used as bioactive additives in commercial products. Besides their antimicrobial activity, nanosafety issues regarding the application of (silver-based) nanoantimicrobials should be considered, as well. In this study, we modified polyurethane foams, typically employed in air filtration and stuffing, by photodeposited silver nanoparticles for preparing hybrid materials (Ag-PU) with antibacterial properties. The composite materials were characterized in terms of morphology, surface chemical composition, ionic release in contact media, bioactivity, as well as whole nanoparticle release. Cytocompatibility was also assessed on 3T3 mouse fibroblasts. The proposed systematic approach allows for defining suitable composite final properties, in terms of bioactivity and safety, by properly tuning the deposition parameters.

Multidrug-resistant organisms are increasingly implicated in acute and chronic wound infections, thus compromising the chance of therapeutic options. The resistance to conventional antibiotics demonstrated by some bacterial strains has encouraged new approaches for the prevention of infections in wounds and burns, among them the use of silver compounds and nanocrystalline silver. Recently, silver wound dressings have become widely accepted in wound healing centers and are commercially available. In this work, novel antibacterial wound dressings have been developed through a silver deposition technology based on the photochemical synthesis of silver nanoparticles. The devices obtained are completely natural and the silver coatings are characterized by an excellent adhesion without the use of any binder. The silver-treated cotton gauzes were characterized through scanning electron microscopy (SEM) and thermo-gravimetric analysis (TGA) in order to verify the distribution and the dimension of the silver particles on the cotton fibers. The effectiveness of the silver-treated gauzes in reducing the bacterial growth and biofilm proliferation has been demonstrated through agar diffusion tests, bacterial enumeration test, biofilm quantification tests, fluorescence and SEM microscopy. Moreover, potential cytotoxicity of the silver coating was evaluated through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide colorimetric assay (MTT) and the extract method on fibroblasts and keratinocytes. Inductively coupled plasma mass spectrometry (ICP-MS) was performed in order to determine the silver release in different media and to relate the results to the biological characterization. All the results obtained were compared with plain gauzes as a negative control, as well as gauzes treated with a higher silver percentage as a positive control.

Over the past several decades, a lot of emerging contaminants have been detected in water and wastewater effluents. Their release should be minimized since their presence in the environment can result in toxic effects for water and human life. Many differ- ent technologies have been used to remove contaminants from drinking water; among them, filtration is one of the most commonly used methods. This study investigated the antibacterial capability of silver water filters and their potential application in the reduction of bacterial fouling and proliferation in water treatment. Poly(ether sulfone) membranes commonly used in water filtration were coated with silver nanoparticles synthesized via the in situ photoreduction method. The morphology of the coating and the distribu- tion of silver clusters were studied by scanning electron microscopy. The amount of silver on the surface was quantified by thermog- ravimetric analysis, and the silver released from the substrate was analyzed through inductively coupled plasma mass spectrometry. The antibacterial capability of the silver-treated filters was demonstrated through microbiological tests defined for the specific applica- tion on Escherichia coli, as the representative coliform bacterium and pathogenic microorganism commonly associated with contami- nated drinking water.