Michele Marini - Academia.edu (original) (raw)
Papers by Michele Marini
Materials Sciences and Applications, 2010
Drug carrier biocompatible and biodegradable nanoparticles of about 15 nm were prepared by solven... more Drug carrier biocompatible and biodegradable nanoparticles of about 15 nm were prepared by solvent evaporation technique from star-shaped poly(D,L-lactide) synthesized using dipentaerythritol as core and Tin (II) ethylhexanoate as catalyst.
Polymer Degradation and Stability, 2008
Packaging Technology and Science, 2008
Polymeric fi lms (low-density polyethylene and oriented polypropylene) for packaging applications... more Polymeric fi lms (low-density polyethylene and oriented polypropylene) for packaging applications coated with organic-inorganic nanocomposite hybrids have been prepared by sol-gel process. Tetraethoxysilane and two different organic phases, polyvinyl alcohol and a diblock copolymer polyethylene-polyethylene glycol were used as precursors. Information about the hydrolysis and polycondensation degrees was obtained by investigating the vibrational features of the coatings by means of attenuated total refl ectance-Fourier transform infrared and Raman spectroscopies. Through a new polariscopic imaging technique, the bidimensional maps of the optical anisotropy of the samples, both as-prepared and under mechanical strain, were obtained. The maps showed inhomogeneous retardation and nearly fl at azimuth distributions. The anisotropy properties of the samples depended mainly on the substrates and were not infl uenced by the coatings, while the optical transmission was slightly better for the tetraethoxysilane-polyvinyl alcohol sample.
Medicinal Chemistry, 2005
Cytochrome P450 1A (CYP1A) is a subclass of enzymes involved in the biotransformation of heterocy... more Cytochrome P450 1A (CYP1A) is a subclass of enzymes involved in the biotransformation of heterocyclic amines present in cooked red meat to carcinogenic compounds. Anti-cancer properties have long been associated with flavonoids, and some compounds of this class have been shown to interact directly with CYP1A2. The understanding of this interaction is the purpose of this work. As the number of experimentally tested molecules is limited, two complementary methods in terms of information provided, are proposed for the study of protein-inhibitor interaction as alternatives to a QSAR analysis, using quantum mechanics as well as molecular mechanics.
Macromolecular Chemistry and Physics, 2008
Polypyrrole-silica nanoparticles were prepared by in situ polymerization of pyrrole monomer in th... more Polypyrrole-silica nanoparticles were prepared by in situ polymerization of pyrrole monomer in the presence of specially modified silica nanoparticles having vinyl functional groups on the surface. The presence of polypyrrole (PPy) on the surface of silica nanoparticles was ...
Journal of Sol-Gel Science and Technology, 2007
Organic–inorganic hybrid materials were prepared through the sol–gel approach starting from tetra... more Organic–inorganic hybrid materials were prepared through the sol–gel approach starting from tetraethoxysilane (TEOS), as silica precursor, and triethoxysilane terminated polymers; before gelling the solutions were applied to polyethylene (PE) films and slabs by spin-coating, without any previous surface pre-treatment of the substrate, and finally the coatings were thermally cured at 60 C for 24 h. Among the various polymers used to prepare the coatings, only polyethylene-b-poly(ethylene glycol) copolymers gave good results in terms of adhesion to the PE substrates, and hybrid coatings with different organic–inorganic ratios were prepared. As suggested by visual inspection and SEM investigation, and confirmed by the critical loads derived from scratch tests, a good adhesion of the coating to the PE substrates was obtained, probably due to the presence of PE segments in the organic phase of the coating. Transparency as well as SEM and DSC data were in agreement with the formation of a nanostructured hybrid coating, with a high level of interpenetration between organic and inorganic domains. It was also observed that these hybrid coatings are able to improve significantly the scratch resistance and slightly increase the wettability with respect to uncoated PE. This approach to the surface-properties modification of PE appears as a simple and convenient method for the functionalization of PE substrates.
Journal of Polymer Science Part A: Polymer Chemistry, 2008
Organic-inorganic hybrid core-shell nanoparticles with diameters ranging from 100 to 1000 nm were... more Organic-inorganic hybrid core-shell nanoparticles with diameters ranging from 100 to 1000 nm were prepared by a one-pot synthesis based on base catalyzed sol-gel reactions using tetraethoxysilane and a triethoxysilane-terminated polyethylene-b-poly(ethylene glycol) as reactants. Data from TEM, TGA, and solid-state NMR analysis are in agreement with the formation of core-shell nanoparticles with an inorganic-rich core and an external shell consisting of an amphiphilic block copolymer monolayer. The influence of the organic-inorganic ratio, solution concentration, and postcuring temperature on core and shell dimensions of the nanospheres were investigated by TEM microscopy. V
Journal of Adhesion Science and Technology, 2013
ABSTRACT
International Journal of Food Microbiology, 2008
In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, wa... more In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, was entrapped in an organic-inorganic hybrid coating applied to a LDPE (low-density polyethylene) film for its potential use in the active food packaging field. The antibacterial activity of the coated film was evaluated against Listeria monocytogenes NCTC 10888 by qualitative modified agar diffusion assay, quantitative determination in listeria saline solution suspension and direct contact with artificially contaminated food samples (frankfurters and fresh cheeses) stored at room and refrigeration temperatures. All investigations demonstrated that enterocin-activated coatings have a good anti-listeria activity. Qualitative tests showed a clear zone of inhibition in the indicator lawn in contact with and around the coated film. During the quantitative antibacterial evaluation the L. monocytogenes viable counts decreased to 1.5 log units compared to the control. The inhibitory capability was confirmed also in food-contact assays. In all food samples packed with coated films we observed a significant decrease in L. monocytogenes viable counts in the first 24 h compared to the control. This difference was generally maintained up to the seventh day and then decreased, with the exception of the cheese samples stored at refrigeration temperature.
European Polymer Journal, 2008
The oxygen barrier properties of composite materials, consisting of a 45 μm thick LDPE substrate ... more The oxygen barrier properties of composite materials, consisting of a 45 μm thick LDPE substrate coated by a thin layer (0.71 μm) of new hybrid organicinorganic materials based on SiO 2 and PE-PEG block copolymers, have been characterized at 35 and 50 °C. A significant ...
European Polymer Journal, 2007
... Solgel solution preparation 2.5. Coating of plastics substrates 2.6. Sample characterization... more ... Solgel solution preparation 2.5. Coating of plastics substrates 2.6. Sample characterization 2.7. ... QAS-Si synthesis 3.2. Coating preparation and application to polymeric substrates 3.3. Antibacterial activity evaluation 4. Conclusions Acknowledgements References. ...
Energy & Fuels, 2013
Corncob and Miscanthus feedstocks were hydrothermally carbonized at 230 °C for 6 h in an autoclav... more Corncob and Miscanthus feedstocks were hydrothermally carbonized at 230 °C for 6 h in an autoclave under autogenous pressure, obtaining fine brown powders with higher carbon and lower hydrogen and oxygen contents than the starting materials. The chemical structure of feedstocks and hydrochars was investigated by 13C cross-polarization magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy complemented by Fourier transform infrared (FTIR) spectroscopy and elemental analysis. In particular, a procedure including CP dynamics analysis and spectral deconvolution was applied to obtain quantitative information on the composition of the analyzed materials from 13C CP-MAS spectra. Miscanthus feedstock contained larger amounts of lignin and crystalline cellulose, which concurred to reduce cellulose exposition to hot water during the hydrothermal carbonization (HTC) process. As a consequence, a lower furan/aromatic ratio was found for Miscanthus versus corncob hydrochars.
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2008
In this work functionally modified silica nanoparticles were synthesized in base-catalyzed reacti... more In this work functionally modified silica nanoparticles were synthesized in base-catalyzed reaction of the elementary molecules: TEOS and vinyltriethoxysilane (VTEOS) using ethanol as the solvent. The main feature of the developed method is the addition of the modifier ...
Materials Sciences and Applications, 2010
Drug carrier biocompatible and biodegradable nanoparticles of about 15 nm were prepared by solven... more Drug carrier biocompatible and biodegradable nanoparticles of about 15 nm were prepared by solvent evaporation technique from star-shaped poly(D,L-lactide) synthesized using dipentaerythritol as core and Tin (II) ethylhexanoate as catalyst.
Polymer Degradation and Stability, 2008
Packaging Technology and Science, 2008
Polymeric fi lms (low-density polyethylene and oriented polypropylene) for packaging applications... more Polymeric fi lms (low-density polyethylene and oriented polypropylene) for packaging applications coated with organic-inorganic nanocomposite hybrids have been prepared by sol-gel process. Tetraethoxysilane and two different organic phases, polyvinyl alcohol and a diblock copolymer polyethylene-polyethylene glycol were used as precursors. Information about the hydrolysis and polycondensation degrees was obtained by investigating the vibrational features of the coatings by means of attenuated total refl ectance-Fourier transform infrared and Raman spectroscopies. Through a new polariscopic imaging technique, the bidimensional maps of the optical anisotropy of the samples, both as-prepared and under mechanical strain, were obtained. The maps showed inhomogeneous retardation and nearly fl at azimuth distributions. The anisotropy properties of the samples depended mainly on the substrates and were not infl uenced by the coatings, while the optical transmission was slightly better for the tetraethoxysilane-polyvinyl alcohol sample.
Medicinal Chemistry, 2005
Cytochrome P450 1A (CYP1A) is a subclass of enzymes involved in the biotransformation of heterocy... more Cytochrome P450 1A (CYP1A) is a subclass of enzymes involved in the biotransformation of heterocyclic amines present in cooked red meat to carcinogenic compounds. Anti-cancer properties have long been associated with flavonoids, and some compounds of this class have been shown to interact directly with CYP1A2. The understanding of this interaction is the purpose of this work. As the number of experimentally tested molecules is limited, two complementary methods in terms of information provided, are proposed for the study of protein-inhibitor interaction as alternatives to a QSAR analysis, using quantum mechanics as well as molecular mechanics.
Macromolecular Chemistry and Physics, 2008
Polypyrrole-silica nanoparticles were prepared by in situ polymerization of pyrrole monomer in th... more Polypyrrole-silica nanoparticles were prepared by in situ polymerization of pyrrole monomer in the presence of specially modified silica nanoparticles having vinyl functional groups on the surface. The presence of polypyrrole (PPy) on the surface of silica nanoparticles was ...
Journal of Sol-Gel Science and Technology, 2007
Organic–inorganic hybrid materials were prepared through the sol–gel approach starting from tetra... more Organic–inorganic hybrid materials were prepared through the sol–gel approach starting from tetraethoxysilane (TEOS), as silica precursor, and triethoxysilane terminated polymers; before gelling the solutions were applied to polyethylene (PE) films and slabs by spin-coating, without any previous surface pre-treatment of the substrate, and finally the coatings were thermally cured at 60 C for 24 h. Among the various polymers used to prepare the coatings, only polyethylene-b-poly(ethylene glycol) copolymers gave good results in terms of adhesion to the PE substrates, and hybrid coatings with different organic–inorganic ratios were prepared. As suggested by visual inspection and SEM investigation, and confirmed by the critical loads derived from scratch tests, a good adhesion of the coating to the PE substrates was obtained, probably due to the presence of PE segments in the organic phase of the coating. Transparency as well as SEM and DSC data were in agreement with the formation of a nanostructured hybrid coating, with a high level of interpenetration between organic and inorganic domains. It was also observed that these hybrid coatings are able to improve significantly the scratch resistance and slightly increase the wettability with respect to uncoated PE. This approach to the surface-properties modification of PE appears as a simple and convenient method for the functionalization of PE substrates.
Journal of Polymer Science Part A: Polymer Chemistry, 2008
Organic-inorganic hybrid core-shell nanoparticles with diameters ranging from 100 to 1000 nm were... more Organic-inorganic hybrid core-shell nanoparticles with diameters ranging from 100 to 1000 nm were prepared by a one-pot synthesis based on base catalyzed sol-gel reactions using tetraethoxysilane and a triethoxysilane-terminated polyethylene-b-poly(ethylene glycol) as reactants. Data from TEM, TGA, and solid-state NMR analysis are in agreement with the formation of core-shell nanoparticles with an inorganic-rich core and an external shell consisting of an amphiphilic block copolymer monolayer. The influence of the organic-inorganic ratio, solution concentration, and postcuring temperature on core and shell dimensions of the nanospheres were investigated by TEM microscopy. V
Journal of Adhesion Science and Technology, 2013
ABSTRACT
International Journal of Food Microbiology, 2008
In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, wa... more In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, was entrapped in an organic-inorganic hybrid coating applied to a LDPE (low-density polyethylene) film for its potential use in the active food packaging field. The antibacterial activity of the coated film was evaluated against Listeria monocytogenes NCTC 10888 by qualitative modified agar diffusion assay, quantitative determination in listeria saline solution suspension and direct contact with artificially contaminated food samples (frankfurters and fresh cheeses) stored at room and refrigeration temperatures. All investigations demonstrated that enterocin-activated coatings have a good anti-listeria activity. Qualitative tests showed a clear zone of inhibition in the indicator lawn in contact with and around the coated film. During the quantitative antibacterial evaluation the L. monocytogenes viable counts decreased to 1.5 log units compared to the control. The inhibitory capability was confirmed also in food-contact assays. In all food samples packed with coated films we observed a significant decrease in L. monocytogenes viable counts in the first 24 h compared to the control. This difference was generally maintained up to the seventh day and then decreased, with the exception of the cheese samples stored at refrigeration temperature.
European Polymer Journal, 2008
The oxygen barrier properties of composite materials, consisting of a 45 μm thick LDPE substrate ... more The oxygen barrier properties of composite materials, consisting of a 45 μm thick LDPE substrate coated by a thin layer (0.71 μm) of new hybrid organicinorganic materials based on SiO 2 and PE-PEG block copolymers, have been characterized at 35 and 50 °C. A significant ...
European Polymer Journal, 2007
... Solgel solution preparation 2.5. Coating of plastics substrates 2.6. Sample characterization... more ... Solgel solution preparation 2.5. Coating of plastics substrates 2.6. Sample characterization 2.7. ... QAS-Si synthesis 3.2. Coating preparation and application to polymeric substrates 3.3. Antibacterial activity evaluation 4. Conclusions Acknowledgements References. ...
Energy & Fuels, 2013
Corncob and Miscanthus feedstocks were hydrothermally carbonized at 230 °C for 6 h in an autoclav... more Corncob and Miscanthus feedstocks were hydrothermally carbonized at 230 °C for 6 h in an autoclave under autogenous pressure, obtaining fine brown powders with higher carbon and lower hydrogen and oxygen contents than the starting materials. The chemical structure of feedstocks and hydrochars was investigated by 13C cross-polarization magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy complemented by Fourier transform infrared (FTIR) spectroscopy and elemental analysis. In particular, a procedure including CP dynamics analysis and spectral deconvolution was applied to obtain quantitative information on the composition of the analyzed materials from 13C CP-MAS spectra. Miscanthus feedstock contained larger amounts of lignin and crystalline cellulose, which concurred to reduce cellulose exposition to hot water during the hydrothermal carbonization (HTC) process. As a consequence, a lower furan/aromatic ratio was found for Miscanthus versus corncob hydrochars.
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2008
In this work functionally modified silica nanoparticles were synthesized in base-catalyzed reacti... more In this work functionally modified silica nanoparticles were synthesized in base-catalyzed reaction of the elementary molecules: TEOS and vinyltriethoxysilane (VTEOS) using ethanol as the solvent. The main feature of the developed method is the addition of the modifier ...