Emanuela Callone | University of Trento (original) (raw)

Papers by Emanuela Callone

Research paper thumbnail of Photocatalytic activity of Eu-doped ZnO prepared by supercritical antisolvent precipitation route: When defects become virtues

Journal of Materials Science & Technology, 2022

Research paper thumbnail of Relazioni filogenetiche all’interno del genere Euplotes (Ciliata, Hypotrichida)

Research paper thumbnail of Variability of lipid membrane composition among different protistan families

Research paper thumbnail of A Versatile Approach to Prepare Layered Silicates Composites: the Case of Sepiolite Nanofibers

Research paper thumbnail of Facile preparation of a cobalt diamine diketonate adduct as a potential vapor phase precursor for Co3O4films

Dalton Transactions, 2021

A novel heteroleptic Co(ii) complex has been synthesized, characterized and successfully evaluate... more A novel heteroleptic Co(ii) complex has been synthesized, characterized and successfully evaluated as a precursor for the CVD of Co3O4 thin films with tailored properties.

Research paper thumbnail of TiO2 containing hybrid nanocomposites with active–passive oxygen scavenging capability

Chemical Engineering Journal, 2021

Abstract Ladder-like silsesquioxanes (SSQs) and TiO2 have been functionalized with methacryloylox... more Abstract Ladder-like silsesquioxanes (SSQs) and TiO2 have been functionalized with methacryloyloxypropyl chains and embedded in a polybutadiene (PB) matrix giving rise to hybrid (organic–inorganic) nanocomposites (NCs) capable of acting as oxygen scavenging materials. The joint use of infrared spectroscopy, small-angle X-ray scattering, and permittivity measurements highlighted that the presence of TiO2, regardless of its modification, does not significantly alter the structure of the NCs, but just reduces the crosslinking degree and induces a local disorganization of the ladder-like SSQ stacks. The introduction of an optimum amount (0.5 wt%) of modified TiO2 within the polymeric matrix enhanced the oxygen uptake rate of ca. 70% with respect to the sole polymeric material. Moreover, the uptake kinetics changes from the first to second order with respect to the PB amount, clearly indicating different oxidation mechanisms. NCs containing modified TiO2 showed an oxygen uptake rate ranging from 30 to 60% higher than that achievable in the presence of bare TiO2. The superior activity of the materials containing modified TiO2 has been related to mechanistic aspects. Fluorescence and electron spin resonance spectroscopies allowed to underline the role of singlet oxygen within the polymeric matrix, although the known photochemical oxidation of PB and the TiO2 induced hydroxyl radical mediated oxidation cannot be excluded. These results open the route to highly efficient flexible oxygen scavenging materials for the protection of electronic devices such as organic based light emitting diodes, solar cells, and liquid crystal displays, which require high targets of protection from oxygen and water.

Research paper thumbnail of Influence of Gd3+ on molecular organization and electrochemical properties of Si-based organic/inorganic sol-gel layers

Electrochimica Acta, 2020

Lanthanoid cations are commonly employed as active corrosion inhibiting agents inside sol-gel coa... more Lanthanoid cations are commonly employed as active corrosion inhibiting agents inside sol-gel coatings derived from organosilanes. However, the effect of lanthanoids on the structure of sol-gel coatings derived from organoalkoxysilanes is still not completely clear and object of debate. Even if it has been reported that lanthanoid ions have a beneficial effect in terms of corrosion protection properties, it has not been completely understood if it is related to the active inhibition of the local electrochemical activity or to a modification of the sol-gel coating structure. In addition, it is still not clear how the lanthanoid ions are distributed in. In order to get some insights into the effect of lanthanoids on the structural and electrochemical properties of sol-gel layers, the present work employs gadolinium ions. Gd was selected also for its magnetic and electronic properties, which strongly affects the signals intensity of many spectroscopy techniques. Accordingly, Gd ions act as a marker to evaluate the localization of lanthanoids in the hybrid network. The structural effect on the sol-gel films promoted by the addition of gadolinium ions has been assessed by means of solid state nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy and electron spin resonance (ESR) spectroscopy. The structural features of the Gd-doped coatings have been correlated with their electrochemical response obtained by means of polarization curves and electrochemical impedance spectroscopy (EIS).

Research paper thumbnail of Silica hairy nanoparticles: a promising material for self-assembling processes

Soft Matter, 2021

“Hairy” nanoparticles (HNPs), i.e. inorganic nanoparticles functionalized with polymer chains, ar... more “Hairy” nanoparticles (HNPs), i.e. inorganic nanoparticles functionalized with polymer chains, are promising building blocks for the synthesis of advanced nanocomposite (NC) materials having several technological applications.

Research paper thumbnail of SiO2/Ladder-Like Polysilsesquioxanes Nanocomposite Coatings: Playing with the Hybrid Interface for Tuning Thermal Properties and Wettability

Coatings, 2020

The present study explores the exploitation of ladder-like polysilsesquioxanes (PSQs) bearing rea... more The present study explores the exploitation of ladder-like polysilsesquioxanes (PSQs) bearing reactive functional groups in conjunction with SiO2 nanoparticles (NPs) to produce UV-curable nanocomposite coatings with increased hydrophobicity and good thermal resistance. In detail, a medium degree regular ladder-like structured poly (methacryloxypropyl) silsesquioxane (LPMASQ) and silica NPs, either naked or functionalized with a methacrylsilane (SiO2@TMMS), were blended and then irradiated in the form of a film. Material characterization evidenced significant modifications of the structural organization of the LPMASQ backbone and, in particular, a rearrangement of the silsesquioxane chains at the interface upon introduction of the functionalized silica NPs. This leads to remarkable thermal resistance and enhanced hydrophobic features in the final nanocomposite. The results suggest that the adopted strategy, in comparison with mostly difficult and expensive surface modification and st...

Research paper thumbnail of Boosting sericin extraction through alternative silk sources

Polymer Journal, 2021

Silk sericin (SS) is a natural polymer widely studied in the design of biodegradable materials fo... more Silk sericin (SS) is a natural polymer widely studied in the design of biodegradable materials for cosmetic, biomedical, food, and chemical applications. This work was designed to explore the molecular and structural characteristics of SS extracted from different silk sources with different processing degrees: high-quality cocoons (NCs), defective cocoons (DCs), and raw silk yarn (Y). The last two sources have been less studied. SS solutions were obtained from each source using the high-temperature and high-pressure degumming method (HTHP). The molecular weight distribution and amino acid composition of SS extracts were determined using gel permeation chromatography (GPC) and reversed-phase chromatography (RP HPLC), respectively. SS films were formed from each solution and then characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), nuclear magnetic resonance spectroscopy (NMR), and differential scanning calorimetry (DSC). Water uptake and degradation of SS films were also evaluated. The molecular characteristics of SS extracts were related to the processing degree of the silk source. Moreover, the properties of SS films seemed to be dominated by the primary structure and the presence of natural impurities in each extract. The results suggest that silk sources could be selected ad hoc to design SS materials with distinctive properties for specific applications. Three different silk sources were explore for sericin (SS) extraction and film formation. Features of each raw material, especially the degree of processing, have remarkable effects on the primary structure and the presence of nonprotein compounds in the sericin extract. As a result, sericin films exhibited distinctive properties that seemed to be correlated with the amount of natural impurities and the molecular properties of the SS extract obtained from each raw material.

Research paper thumbnail of Thin Films of Plasma-Polymerized n-Hexane and ZnO Nanoparticles Co-Deposited via Atmospheric Pressure Plasma Jet

Coatings, 2021

This study explores the co-deposition of thin polymeric films loaded with nanoparticles for its p... more This study explores the co-deposition of thin polymeric films loaded with nanoparticles for its possible future application as radiation detectors. Thin films containing zinc oxide (ZnO) nanoparticles in plasma polymerized n-hexane (PPH) were deposited on silicon substrates using an atmospheric pressure plasma jet (APPJ). Crystalline ZnO nanoparticles were produced by wet chemistry, characterized, and injected through the plasma with an aerosol buffer. The precursor hydrocarbon was polymerized in atmosphere at room temperature by the plasma, resulting in a highly crosslinked structure chemically stable against common solvents. The polymer structure was characterized by FT-IR, NMR, and thermal analyses. Photoluminescence analysis revealed that ZnO UV excitonic emission is recovered owing to the passivation through polymeric encapsulation, with a remarkable increase in luminescence yield.

Research paper thumbnail of A community-built calibration system: The case study of quantification of metabolites in grape juice by qNMR spectroscopy

Talanta, 2020

Nuclear Magnetic Resonance (NMR) is an analytical technique extensively used in almost every chem... more Nuclear Magnetic Resonance (NMR) is an analytical technique extensively used in almost every chemical laboratory for structural identification. This technique provides statistically equivalent signals in spite of using spectrometer with different hardware features and is successfully used for the traceability and quantification of analytes in food samples. Nevertheless, to date only a few internationally agreed guidelines have been reported on the use of NMR for quantitative analysis. The main goal of the present study is to provide a methodological pipeline to assess the reproducibility of NMR data produced for a given matrix by spectrometers from different manufacturers, with different magnetic field strengths, age and hardware configurations. The results have been analyzed through a sequence of chemometric tests to generate a community-built calibration system which was used to verify the performance of the spectrometers and the reproducibility of the predicted sample concentrations.

Research paper thumbnail of Nanopowders of Metallic Oxides Prepared by the Hydrolytic Route with Starch Stabilization and Biological Abetment

Journal of Nanoscience and Nanotechnology, 2006

Sn, Sn–Sb, Ti, Zr, Fe, Ce and In oxides are prepared as nanometric powders by the hydrolytic rout... more Sn, Sn–Sb, Ti, Zr, Fe, Ce and In oxides are prepared as nanometric powders by the hydrolytic route, starting from their ordinary salts or alkoxides, in the presence of 5% w/v starch as a non-ionic stabilizer of crystallization nuclei versus coalescence and flocculation. The starch can be degraded by α-amylase to soluble glucosidic oligomers, which may further be degraded by yeast to CO2 and ethanol. The nanoparticle features of prepared oxides result from experimental evidence based on X-ray diffractometry, transmission electron microscopy, differential thermal analysis/thermogravimetry coupled to mass spectrometry, specific surface area and porosity of samples obtained by curing in the 80–600 °C interval.

Research paper thumbnail of Effect of the Organic Functional Group on the Grafting Ability of Trialkoxysilanes onto Graphene Oxide: A Combined NMR, XRD, and ESR Study

Materials, 2019

The functional properties displayed by graphene oxide (GO)-polymer nanocomposites are strongly af... more The functional properties displayed by graphene oxide (GO)-polymer nanocomposites are strongly affected by the dispersion ability of GO sheets in the polymeric matrix, which can be largely improved by functionalization with organosilanes. The grafting to GO of organosilanes with the general formula RSi(OCH3)3 is generally explained by the condensation reactions of silanols with GO reactive groups. In this study, the influence of the organic group on the RSi(OCH3)3 grafting ability was analyzed in depth, taking into account the interactions of the R end chain group with GO oxidized groups. Model systems composed of commercial graphene oxide reacted with 3-aminopropyltrimethoxysilane (APTMS), 3-mercaptopropyltrimethoxysilane (MPTMS), and 3-methacryloxypropyltrimethoxysilane, (MaPTMS), respectively, were characterized by natural abundance 13C, 15N and 29Si solid state nuclear magnetic resonance (NMR), x-ray diffraction (XRD), and electron spin resonance (ESR). The silane organic tail s...

Research paper thumbnail of Tailoring the Dielectric and Mechanical Properties of Polybutadiene Nanocomposites by Using Designed Ladder-like Polysilsesquioxanes

ACS Applied Nano Materials, 2018

Research paper thumbnail of Docosane-Organosilica Microcapsules for Structural Composites with Thermal Energy Storage/Release Capability

Materials, 2019

Organic phase change materials (PCMs) represent an effective solution to manage intermittent ener... more Organic phase change materials (PCMs) represent an effective solution to manage intermittent energy sources as the solar thermal energy. This work aims at encapsulating docosane in organosilica shells and at dispersing the produced capsules in epoxy/carbon laminates to manufacture multifunctional structural composites for thermal energy storage (TES). Microcapsules of different sizes were prepared by hydrolysis-condensation of methyltriethoxysilane (MTES) in an oil-in-water emulsion. X-ray diffraction (XRD) highlighted the difference in the crystalline structure of pristine and microencapsulated docosane, and 13C solid-state nuclear magnetic resonance (NMR) evidenced the influence of microcapsules size on the shifts of the representative docosane signals, as a consequence of confinement effects, i.e., reduced chain mobility and interaction with the inner shell walls. A phase change enthalpy up to 143 J/g was determined via differential scanning calorimetry (DSC) on microcapsules, an...

Research paper thumbnail of Structure of Cellulose Isolated from Rapeseed (Brassica Napus L.) Stalks

We characterized for the first time the rapeseed stalk’s cellulose and it has been found that nat... more We characterized for the first time the rapeseed stalk’s cellulose and it has been found that native cellulose occurs as Cellulose I allomorph, while α-cellulose consists of particular crystalline structures as seen in cellulose II.

Research paper thumbnail of Silk Fibroin Porous Scaffolds Loaded with a Slow-Releasing Hydrogen Sulfide Agent (GYY4137) for Applications of Tissue Engineering

ACS Biomaterials Science & Engineering, 2018

Hydrogen sulfide (H 2 S) is a physiological gasotransmitter known to possess a regulatory role in... more Hydrogen sulfide (H 2 S) is a physiological gasotransmitter known to possess a regulatory role in several tissues, including bone. The exogenous administration by injection of solutions of H 2 S-releasing compounds (e.g., GYY4137) has been previously investigated as a novel therapeutic approach for the treatment of bone diseases. Here, GYY4137 was embedded into fibroin sponges, previously shown to be suitable as scaffolds for bone, thanks to their biocompatibility, scalable porous structure, and biodegradability rate. Fibroin porous scaffolds were produced by solvent casting and the particulate leaching method, and GYY4137 was successively incorporated by using dimethyl sulfoxide (DMSO) as vehicle. The process used to produce GYY4137-loaded scaffolds allowed the incorporation of different controlled amounts of GYY4137 into fibroin matrices. The loading process preserved the properties of the system components in the final products, as assessed by SEM, FT-IR, NMR, and different thermal analyses techniques. Release of H 2 S from GYY4137 incorporated into the scaffolds was monitored upon incubation in saline solution at physiological pH: H 2 S-release kinetic was found to be dependent on the amount of GYY4137. To ensure biocompatibility, mouse fibroblasts and human primary bone marrow stromal cells were seeded onto scaffolds, and short-term viability assays were performed. Results showed that the GYY4137-loaded scaffold did not induce cytotoxicity in any of the cell type tested. Our findings demonstrate that embedding an H 2 S-releasing donor in silk fibroin scaffold is a suitable strategy to achieve a long-lasting release of H 2 S that preserves cell viability and allows local delivery at sites of tissue injury.

Research paper thumbnail of Filler-matrix interaction in sodium montmorillonite-organosilica nanocomposite coatings for corrosion protection

Applied Clay Science, 2017

Sodium montmorillonite/organosilica sol-gel coatings were obtained from a hydrolysed solution of ... more Sodium montmorillonite/organosilica sol-gel coatings were obtained from a hydrolysed solution of 3-glycidoxypropyltrimethoxysilane (GPTMS), methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS) with 2 wt% of sonicated sodium montmorillonite (Mt). The effect of different sonication times (0, 1, 3, 12 h) on the structure of both Mt and sol-gel clay-organosilica nanocomposites was investigated by means of 29 Si and 27 Al solid state nuclear magnetic resonance (NMR) and X-ray diffraction (XRD). Mt underwent relevant structural changes with the sonication treatment and the effect appeared time-dependent, although not linear. The structural changes induced on clay by the sonication process were kept in the clay-organosilica nanocomposite, according to 29 Si NMR. Mt addition to the hybrid sol-gel network led to decreasing the amount of completely condensed silicon units by formation of new Si-O-Al hetero-metallic bonds, as shown by 27 Al NMR results. Moreover, organosilica matrix and Mt appeared to interact even in the absence of the sonication treatment of the filler. The NMR study of GPTMS/MTES/Mt and TEOS/Mt samples clearly proves the interaction of Mt with the silsesquioxane (T) species in the obtained composites.

Research paper thumbnail of Properties of anion exchange membrane based on polyamine: Effect of functionalized silica particles prepared by sol–gel method

Solid State Ionics, 2018

Membranes of polyamine (PA-SiNH 2) m , containing silica reacted with 3-aminopropyltriethoxysilan... more Membranes of polyamine (PA-SiNH 2) m , containing silica reacted with 3-aminopropyltriethoxysilane (APTES) in hydrolytic conditions were prepared via solution casting, followed by methylation and ion exchange process. The influence of amino-functionalized silica (Si-NH 2) on the properties of the obtained membrane was investigated. Fourier transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance spectroscopy (NMR) were used to investigate the chemical features of the silica and its interaction with the polyamine polymer. The results of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) of the modified membrane confirmed it is stable up to 300°C. The thermal stability is the result of the interaction of modified silica particles and polyamine polymer. It was demonstrated that the performance of the (PA-SiNH 2) m anion exchange membrane is greatly improved by incorporation of silica nanoparticles as compared with the anion exchange membrane (PK-PDAPm), which doesn't contain silica. Therefore, the (PA-SiNH 2) m is a suitable candidate for electrochemical applications.

Research paper thumbnail of Photocatalytic activity of Eu-doped ZnO prepared by supercritical antisolvent precipitation route: When defects become virtues

Journal of Materials Science & Technology, 2022

Research paper thumbnail of Relazioni filogenetiche all’interno del genere Euplotes (Ciliata, Hypotrichida)

Research paper thumbnail of Variability of lipid membrane composition among different protistan families

Research paper thumbnail of A Versatile Approach to Prepare Layered Silicates Composites: the Case of Sepiolite Nanofibers

Research paper thumbnail of Facile preparation of a cobalt diamine diketonate adduct as a potential vapor phase precursor for Co3O4films

Dalton Transactions, 2021

A novel heteroleptic Co(ii) complex has been synthesized, characterized and successfully evaluate... more A novel heteroleptic Co(ii) complex has been synthesized, characterized and successfully evaluated as a precursor for the CVD of Co3O4 thin films with tailored properties.

Research paper thumbnail of TiO2 containing hybrid nanocomposites with active–passive oxygen scavenging capability

Chemical Engineering Journal, 2021

Abstract Ladder-like silsesquioxanes (SSQs) and TiO2 have been functionalized with methacryloylox... more Abstract Ladder-like silsesquioxanes (SSQs) and TiO2 have been functionalized with methacryloyloxypropyl chains and embedded in a polybutadiene (PB) matrix giving rise to hybrid (organic–inorganic) nanocomposites (NCs) capable of acting as oxygen scavenging materials. The joint use of infrared spectroscopy, small-angle X-ray scattering, and permittivity measurements highlighted that the presence of TiO2, regardless of its modification, does not significantly alter the structure of the NCs, but just reduces the crosslinking degree and induces a local disorganization of the ladder-like SSQ stacks. The introduction of an optimum amount (0.5 wt%) of modified TiO2 within the polymeric matrix enhanced the oxygen uptake rate of ca. 70% with respect to the sole polymeric material. Moreover, the uptake kinetics changes from the first to second order with respect to the PB amount, clearly indicating different oxidation mechanisms. NCs containing modified TiO2 showed an oxygen uptake rate ranging from 30 to 60% higher than that achievable in the presence of bare TiO2. The superior activity of the materials containing modified TiO2 has been related to mechanistic aspects. Fluorescence and electron spin resonance spectroscopies allowed to underline the role of singlet oxygen within the polymeric matrix, although the known photochemical oxidation of PB and the TiO2 induced hydroxyl radical mediated oxidation cannot be excluded. These results open the route to highly efficient flexible oxygen scavenging materials for the protection of electronic devices such as organic based light emitting diodes, solar cells, and liquid crystal displays, which require high targets of protection from oxygen and water.

Research paper thumbnail of Influence of Gd3+ on molecular organization and electrochemical properties of Si-based organic/inorganic sol-gel layers

Electrochimica Acta, 2020

Lanthanoid cations are commonly employed as active corrosion inhibiting agents inside sol-gel coa... more Lanthanoid cations are commonly employed as active corrosion inhibiting agents inside sol-gel coatings derived from organosilanes. However, the effect of lanthanoids on the structure of sol-gel coatings derived from organoalkoxysilanes is still not completely clear and object of debate. Even if it has been reported that lanthanoid ions have a beneficial effect in terms of corrosion protection properties, it has not been completely understood if it is related to the active inhibition of the local electrochemical activity or to a modification of the sol-gel coating structure. In addition, it is still not clear how the lanthanoid ions are distributed in. In order to get some insights into the effect of lanthanoids on the structural and electrochemical properties of sol-gel layers, the present work employs gadolinium ions. Gd was selected also for its magnetic and electronic properties, which strongly affects the signals intensity of many spectroscopy techniques. Accordingly, Gd ions act as a marker to evaluate the localization of lanthanoids in the hybrid network. The structural effect on the sol-gel films promoted by the addition of gadolinium ions has been assessed by means of solid state nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy and electron spin resonance (ESR) spectroscopy. The structural features of the Gd-doped coatings have been correlated with their electrochemical response obtained by means of polarization curves and electrochemical impedance spectroscopy (EIS).

Research paper thumbnail of Silica hairy nanoparticles: a promising material for self-assembling processes

Soft Matter, 2021

“Hairy” nanoparticles (HNPs), i.e. inorganic nanoparticles functionalized with polymer chains, ar... more “Hairy” nanoparticles (HNPs), i.e. inorganic nanoparticles functionalized with polymer chains, are promising building blocks for the synthesis of advanced nanocomposite (NC) materials having several technological applications.

Research paper thumbnail of SiO2/Ladder-Like Polysilsesquioxanes Nanocomposite Coatings: Playing with the Hybrid Interface for Tuning Thermal Properties and Wettability

Coatings, 2020

The present study explores the exploitation of ladder-like polysilsesquioxanes (PSQs) bearing rea... more The present study explores the exploitation of ladder-like polysilsesquioxanes (PSQs) bearing reactive functional groups in conjunction with SiO2 nanoparticles (NPs) to produce UV-curable nanocomposite coatings with increased hydrophobicity and good thermal resistance. In detail, a medium degree regular ladder-like structured poly (methacryloxypropyl) silsesquioxane (LPMASQ) and silica NPs, either naked or functionalized with a methacrylsilane (SiO2@TMMS), were blended and then irradiated in the form of a film. Material characterization evidenced significant modifications of the structural organization of the LPMASQ backbone and, in particular, a rearrangement of the silsesquioxane chains at the interface upon introduction of the functionalized silica NPs. This leads to remarkable thermal resistance and enhanced hydrophobic features in the final nanocomposite. The results suggest that the adopted strategy, in comparison with mostly difficult and expensive surface modification and st...

Research paper thumbnail of Boosting sericin extraction through alternative silk sources

Polymer Journal, 2021

Silk sericin (SS) is a natural polymer widely studied in the design of biodegradable materials fo... more Silk sericin (SS) is a natural polymer widely studied in the design of biodegradable materials for cosmetic, biomedical, food, and chemical applications. This work was designed to explore the molecular and structural characteristics of SS extracted from different silk sources with different processing degrees: high-quality cocoons (NCs), defective cocoons (DCs), and raw silk yarn (Y). The last two sources have been less studied. SS solutions were obtained from each source using the high-temperature and high-pressure degumming method (HTHP). The molecular weight distribution and amino acid composition of SS extracts were determined using gel permeation chromatography (GPC) and reversed-phase chromatography (RP HPLC), respectively. SS films were formed from each solution and then characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), nuclear magnetic resonance spectroscopy (NMR), and differential scanning calorimetry (DSC). Water uptake and degradation of SS films were also evaluated. The molecular characteristics of SS extracts were related to the processing degree of the silk source. Moreover, the properties of SS films seemed to be dominated by the primary structure and the presence of natural impurities in each extract. The results suggest that silk sources could be selected ad hoc to design SS materials with distinctive properties for specific applications. Three different silk sources were explore for sericin (SS) extraction and film formation. Features of each raw material, especially the degree of processing, have remarkable effects on the primary structure and the presence of nonprotein compounds in the sericin extract. As a result, sericin films exhibited distinctive properties that seemed to be correlated with the amount of natural impurities and the molecular properties of the SS extract obtained from each raw material.

Research paper thumbnail of Thin Films of Plasma-Polymerized n-Hexane and ZnO Nanoparticles Co-Deposited via Atmospheric Pressure Plasma Jet

Coatings, 2021

This study explores the co-deposition of thin polymeric films loaded with nanoparticles for its p... more This study explores the co-deposition of thin polymeric films loaded with nanoparticles for its possible future application as radiation detectors. Thin films containing zinc oxide (ZnO) nanoparticles in plasma polymerized n-hexane (PPH) were deposited on silicon substrates using an atmospheric pressure plasma jet (APPJ). Crystalline ZnO nanoparticles were produced by wet chemistry, characterized, and injected through the plasma with an aerosol buffer. The precursor hydrocarbon was polymerized in atmosphere at room temperature by the plasma, resulting in a highly crosslinked structure chemically stable against common solvents. The polymer structure was characterized by FT-IR, NMR, and thermal analyses. Photoluminescence analysis revealed that ZnO UV excitonic emission is recovered owing to the passivation through polymeric encapsulation, with a remarkable increase in luminescence yield.

Research paper thumbnail of A community-built calibration system: The case study of quantification of metabolites in grape juice by qNMR spectroscopy

Talanta, 2020

Nuclear Magnetic Resonance (NMR) is an analytical technique extensively used in almost every chem... more Nuclear Magnetic Resonance (NMR) is an analytical technique extensively used in almost every chemical laboratory for structural identification. This technique provides statistically equivalent signals in spite of using spectrometer with different hardware features and is successfully used for the traceability and quantification of analytes in food samples. Nevertheless, to date only a few internationally agreed guidelines have been reported on the use of NMR for quantitative analysis. The main goal of the present study is to provide a methodological pipeline to assess the reproducibility of NMR data produced for a given matrix by spectrometers from different manufacturers, with different magnetic field strengths, age and hardware configurations. The results have been analyzed through a sequence of chemometric tests to generate a community-built calibration system which was used to verify the performance of the spectrometers and the reproducibility of the predicted sample concentrations.

Research paper thumbnail of Nanopowders of Metallic Oxides Prepared by the Hydrolytic Route with Starch Stabilization and Biological Abetment

Journal of Nanoscience and Nanotechnology, 2006

Sn, Sn–Sb, Ti, Zr, Fe, Ce and In oxides are prepared as nanometric powders by the hydrolytic rout... more Sn, Sn–Sb, Ti, Zr, Fe, Ce and In oxides are prepared as nanometric powders by the hydrolytic route, starting from their ordinary salts or alkoxides, in the presence of 5% w/v starch as a non-ionic stabilizer of crystallization nuclei versus coalescence and flocculation. The starch can be degraded by α-amylase to soluble glucosidic oligomers, which may further be degraded by yeast to CO2 and ethanol. The nanoparticle features of prepared oxides result from experimental evidence based on X-ray diffractometry, transmission electron microscopy, differential thermal analysis/thermogravimetry coupled to mass spectrometry, specific surface area and porosity of samples obtained by curing in the 80–600 °C interval.

Research paper thumbnail of Effect of the Organic Functional Group on the Grafting Ability of Trialkoxysilanes onto Graphene Oxide: A Combined NMR, XRD, and ESR Study

Materials, 2019

The functional properties displayed by graphene oxide (GO)-polymer nanocomposites are strongly af... more The functional properties displayed by graphene oxide (GO)-polymer nanocomposites are strongly affected by the dispersion ability of GO sheets in the polymeric matrix, which can be largely improved by functionalization with organosilanes. The grafting to GO of organosilanes with the general formula RSi(OCH3)3 is generally explained by the condensation reactions of silanols with GO reactive groups. In this study, the influence of the organic group on the RSi(OCH3)3 grafting ability was analyzed in depth, taking into account the interactions of the R end chain group with GO oxidized groups. Model systems composed of commercial graphene oxide reacted with 3-aminopropyltrimethoxysilane (APTMS), 3-mercaptopropyltrimethoxysilane (MPTMS), and 3-methacryloxypropyltrimethoxysilane, (MaPTMS), respectively, were characterized by natural abundance 13C, 15N and 29Si solid state nuclear magnetic resonance (NMR), x-ray diffraction (XRD), and electron spin resonance (ESR). The silane organic tail s...

Research paper thumbnail of Tailoring the Dielectric and Mechanical Properties of Polybutadiene Nanocomposites by Using Designed Ladder-like Polysilsesquioxanes

ACS Applied Nano Materials, 2018

Research paper thumbnail of Docosane-Organosilica Microcapsules for Structural Composites with Thermal Energy Storage/Release Capability

Materials, 2019

Organic phase change materials (PCMs) represent an effective solution to manage intermittent ener... more Organic phase change materials (PCMs) represent an effective solution to manage intermittent energy sources as the solar thermal energy. This work aims at encapsulating docosane in organosilica shells and at dispersing the produced capsules in epoxy/carbon laminates to manufacture multifunctional structural composites for thermal energy storage (TES). Microcapsules of different sizes were prepared by hydrolysis-condensation of methyltriethoxysilane (MTES) in an oil-in-water emulsion. X-ray diffraction (XRD) highlighted the difference in the crystalline structure of pristine and microencapsulated docosane, and 13C solid-state nuclear magnetic resonance (NMR) evidenced the influence of microcapsules size on the shifts of the representative docosane signals, as a consequence of confinement effects, i.e., reduced chain mobility and interaction with the inner shell walls. A phase change enthalpy up to 143 J/g was determined via differential scanning calorimetry (DSC) on microcapsules, an...

Research paper thumbnail of Structure of Cellulose Isolated from Rapeseed (Brassica Napus L.) Stalks

We characterized for the first time the rapeseed stalk’s cellulose and it has been found that nat... more We characterized for the first time the rapeseed stalk’s cellulose and it has been found that native cellulose occurs as Cellulose I allomorph, while α-cellulose consists of particular crystalline structures as seen in cellulose II.

Research paper thumbnail of Silk Fibroin Porous Scaffolds Loaded with a Slow-Releasing Hydrogen Sulfide Agent (GYY4137) for Applications of Tissue Engineering

ACS Biomaterials Science & Engineering, 2018

Hydrogen sulfide (H 2 S) is a physiological gasotransmitter known to possess a regulatory role in... more Hydrogen sulfide (H 2 S) is a physiological gasotransmitter known to possess a regulatory role in several tissues, including bone. The exogenous administration by injection of solutions of H 2 S-releasing compounds (e.g., GYY4137) has been previously investigated as a novel therapeutic approach for the treatment of bone diseases. Here, GYY4137 was embedded into fibroin sponges, previously shown to be suitable as scaffolds for bone, thanks to their biocompatibility, scalable porous structure, and biodegradability rate. Fibroin porous scaffolds were produced by solvent casting and the particulate leaching method, and GYY4137 was successively incorporated by using dimethyl sulfoxide (DMSO) as vehicle. The process used to produce GYY4137-loaded scaffolds allowed the incorporation of different controlled amounts of GYY4137 into fibroin matrices. The loading process preserved the properties of the system components in the final products, as assessed by SEM, FT-IR, NMR, and different thermal analyses techniques. Release of H 2 S from GYY4137 incorporated into the scaffolds was monitored upon incubation in saline solution at physiological pH: H 2 S-release kinetic was found to be dependent on the amount of GYY4137. To ensure biocompatibility, mouse fibroblasts and human primary bone marrow stromal cells were seeded onto scaffolds, and short-term viability assays were performed. Results showed that the GYY4137-loaded scaffold did not induce cytotoxicity in any of the cell type tested. Our findings demonstrate that embedding an H 2 S-releasing donor in silk fibroin scaffold is a suitable strategy to achieve a long-lasting release of H 2 S that preserves cell viability and allows local delivery at sites of tissue injury.

Research paper thumbnail of Filler-matrix interaction in sodium montmorillonite-organosilica nanocomposite coatings for corrosion protection

Applied Clay Science, 2017

Sodium montmorillonite/organosilica sol-gel coatings were obtained from a hydrolysed solution of ... more Sodium montmorillonite/organosilica sol-gel coatings were obtained from a hydrolysed solution of 3-glycidoxypropyltrimethoxysilane (GPTMS), methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS) with 2 wt% of sonicated sodium montmorillonite (Mt). The effect of different sonication times (0, 1, 3, 12 h) on the structure of both Mt and sol-gel clay-organosilica nanocomposites was investigated by means of 29 Si and 27 Al solid state nuclear magnetic resonance (NMR) and X-ray diffraction (XRD). Mt underwent relevant structural changes with the sonication treatment and the effect appeared time-dependent, although not linear. The structural changes induced on clay by the sonication process were kept in the clay-organosilica nanocomposite, according to 29 Si NMR. Mt addition to the hybrid sol-gel network led to decreasing the amount of completely condensed silicon units by formation of new Si-O-Al hetero-metallic bonds, as shown by 27 Al NMR results. Moreover, organosilica matrix and Mt appeared to interact even in the absence of the sonication treatment of the filler. The NMR study of GPTMS/MTES/Mt and TEOS/Mt samples clearly proves the interaction of Mt with the silsesquioxane (T) species in the obtained composites.

Research paper thumbnail of Properties of anion exchange membrane based on polyamine: Effect of functionalized silica particles prepared by sol–gel method

Solid State Ionics, 2018

Membranes of polyamine (PA-SiNH 2) m , containing silica reacted with 3-aminopropyltriethoxysilan... more Membranes of polyamine (PA-SiNH 2) m , containing silica reacted with 3-aminopropyltriethoxysilane (APTES) in hydrolytic conditions were prepared via solution casting, followed by methylation and ion exchange process. The influence of amino-functionalized silica (Si-NH 2) on the properties of the obtained membrane was investigated. Fourier transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance spectroscopy (NMR) were used to investigate the chemical features of the silica and its interaction with the polyamine polymer. The results of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) of the modified membrane confirmed it is stable up to 300°C. The thermal stability is the result of the interaction of modified silica particles and polyamine polymer. It was demonstrated that the performance of the (PA-SiNH 2) m anion exchange membrane is greatly improved by incorporation of silica nanoparticles as compared with the anion exchange membrane (PK-PDAPm), which doesn't contain silica. Therefore, the (PA-SiNH 2) m is a suitable candidate for electrochemical applications.