Bio-plastics are starting to graduate from the 'emerging technology' stage to market acceptance as everyday materials. In the present study, nanocomposite coatings embedding copper nanoparticles (CuNPs) were developed as new active packaging for fresh dairy products. In order to combine the bioactivity of CuNPs with a biodegradable polymer matrix, copper nanoparticles were satisfactorily incorporated into polylactic acid (PLA). Two different routes were carried out to prepare active films by picosecond-pulsed laser ablation. The nano-materials were characterized by UV-Vis spectroscopy and X-ray Photoelectron spectroscopy. Copper release was also measured through atomic absorption analyses. To assess the antimicrobial effects of nanocomposite systems, both in vitro and in vivo tests were carried out. The active polylactic acid films showed good antibacterial activity. In fiordilatte samples stored at 4 C during 9 days, proliferation of main spoilage microorganisms was delayed with a consequent preservation of sensory attributes. These results represent a step forward in the possible application of copper in the food packaging industry. Industrial relevance Bio-plastics with active properties represent the most emerging technology in food packaging field. Results from the current paper demonstrate that antimicrobial films of PLA embedding copper nanoparticles could be developed and applied to fresh dairy products as fiordilatte. In fact, the in vivo test confirmed the antimicrobial effects on fiordilatte spoilage, without compromising sensory attributes. Results could gain great importance from the industrial dairy sector.

Smart, MEMS-based biosensors are a promising new platform for the delivery of diagnostic services, but inclusion of on-chip CMOS electronics requires the definition a CMOS compatible techniques for the bio-activation of the sensor surface. In this work, a comparison between a sensor functionalization procedure by complete immersion of the sensor chip or by exposure to a single drop of the reagents (the latter approach being more compatible with the presence of on-chip CMOS components) is presented.

A new type of nanomaterial has been developed as antibacterial additive for food packaging applications. This nanocomposite is composed of copper nanoparticles embedded in polylactic acid, combining the antibacterial properties of copper nanoparticles with the biodegradability of the polymer matrix. Metal nanoparticles have been synthesised by means of laser ablation, a rising and easy route to prepare nanostructures without any capping agent in a liquid environment. As prepared, nanoparticle suspensions have been easily mixed to a polymer solution. The resulting hybrid solutions have been deposited by drop casting, thus obtaining self-standing antibacterial packages. All samples have been characterized by UV-Vis spectroscopy, X-ray photoelectron spectroscopy and electro-thermal atomic absorption spectroscopy. Ion release data have been matched with bioactivity tests performed by Japanese Industrial Standard (JIS) method (JIS Z 2801:2000) against Pseudomonas spp., a very common Gram-negative microbial group able to proliferate in processed food.

Gold nanoparticles stabilized on metal oxide supports have found a wide range of applications especially in heterogeneous catalysis and gas sensing. A facile methodology for the in situ electrodecoration of gold nanoparticles on metal oxide supports is presented herein. Metal oxides such as indium oxide (In2O3) and zirconia (ZrO2) nanoparticles are first prepared via the sol-gel route. Subsequently, gold nanoparticles are electrodeposited in situ on the surface of these metal oxides using a modified sacrificial Au-anode electrolysis procedure. Both pristine as well as electrodecorated metal oxides are characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM, TEM). SEM images of electrodecorated metal oxides reveal successful deposition of gold nanoparticles on metal oxide supports. XPS shows that nano-sized gold is significantly available on the materials' surface and it is in the elemental oxidation state. Moreover, it is found that the electrodecoration of gold nanoparticles on metal oxide surfaces proceeds as a function of the concentration of hydroxyl groups on the surface of metal oxide supports.

Methods to immobilize proteins are of particular relevance for biosensing. In biosensors, proteins have to be assembled according to suitable architectures on solid surfaces such as electrodes, optical windows, or the organic semiconductor layer of electronic devices and their integrity and activity have to be preserved. This chapter deals with the use of immobilized proteins in several types of biosensors. The importance of molecular architecture control, particularly with synergistic combination of proteins and “other” materials, is evidenced. Different methodologies for protein assembly are described, highlighting the environmental applications of the protein based biosensors. Results from the literature, grouped into large areas covering optical and electrochemical biosensors and also sensing exploiting field-effect transistors, are reported. Layer by layer (LbL) immobilization of proteins on the transparent substrate of optical biosensors is proposed for its advantageous control of molecular architecture and versatility to accommodate layers having different functionalities. Covalent immobilization is evaluated as an alternative process for the controlled incorporation of the recognition element on/into the electrode surface, in the case of electrochemical transducers. Finally, the integration of immobilized proteins in electronic devices is presented, especially in the context of using field-effect transistors (FETs) for biosensing. It is hoped that this survey may assist researchers in choosing materials, molecular architectures, and detection principles, which may be tailored for specific applications.

Bio-sensing represents one of the most attractive applications of carbon material based electronic devices; nevertheless, the complete integration of bioactive transducing elements still represents a major challenge, particularly in terms of preserving biological function and specificity while maintaining the sensor’s electronic performance. This review highlights recent advances in the realization of field-effect transistor (FET) based sensors that comprise a bio-receptor within the FET channel. A birds-eye view will be provided of the most promising classes of active layers as well as different device architectures and methods of fabrication. Finally, strategies for interfacing bio-components with organic or carbon nanostructured electronic active layers are reported.

Synthesis and fabrication and assembly of functional particles and capsules Material Research Society, San Francisco (USA), April 2012

Gold (Au) nanoparticles stabilized on metal oxide supports offer superior catalytic activity and recyclability in organic catalysis. We report for the first time synthesis of indium oxide stabilized gold (Au@In2O 3) nanocatalysts using an electrochemical procedure and their application in homocoupling of arylboronic acids. In2O3 nanoparticles prepared via sol-gel process are subjected to sacrificial anode electrolysis (SAE) under inert condition for electrodeposition of nano Au on In2O3. Thus Au@In2O3 nanoparticles obtained are thermally annealed at high temperature to partially oxidize Au and to remove any surfactants. XPS results show the existence of both elemental (nano Au0) and cationic (Au3+) species in Au@In 2O3 nanocatalysts, while SEM images confirm the presence of nanoscale Au (<10 nm) particles on In2O3 surface. Au@In2O3 nanocatalysts are tested for arylboronic acids homocoupling under different conditions and it is found that they are highly active in organic medium with K2CO3 base and demonstrate excellent conversion (>97%) and selectivity (>98%). The catalyst recyclability and performance towards differently substituted arylboronic acids is also studied and a plausible mechanism of action is proposed.

The present work is aimed at developing gold nanostructures functionalized with antenna systems to exploit the synergistic nanostructure/antenna desorption-ionization efficiency. A potential Matrix- Assisted Laser Desorption Ionisation (MALDI) organic matrix has been modified introducing specific functional groups or molecular linker and used as a capping agent for gold nanostructures. In particular, conjugated naphthyl-thio-derivative, i.e. 4-mercaptonaphthalene-1,8-dicarboxylic acid, was synthesized and characterized by means of nuclear magnetic resonance, UVevisible and X-ray photoelectron spectroscopies. Afterwards, the thio-derivative was used as covalent surface modifier for flat gold surfaces and nanostructured gold films. These surfaces were thoroughly characterized by means of parallel angle-resolved X-ray photoelectron spectroscopy to obtain quantitative information about elemental composition, chemical speciation, and in-depth distribution of the target chemical functional groups. Finally the compound was preliminarily tested as a non-conventional matrix in Laser Desorption Ionisation Mass Spectrometry (LDI-MS) analysis of low molecular weight biomolecules in order to assess its capability of acting as the antenna system and proton donor after covalent bonding to gold nanomaterials.

Automobile exhaust gas emissions are causing serious damage to urban air quality in and around major cities of the world, which demands continuous monitoring of exhaust emissions. The chief components of automobile exhaust include carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbons. Indium zirconate (InZrOx) and gold/indium zirconate (Au/InZrOx) composite nanopowders are believed to be interesting materials to detect these substances. To this end, characterization and gas sensing properties of InZrOx and Au/InZrOx composite nanopowders are discussed. InZrOx nanoparticles with In/Zr atomic ratio of 1.00 (±0.05) are synthesized via pH-controlled co-precipitation of In and Zr salts in aqueous ammonia. Gold (Au) nanoparticles are subsequently deposited on InZrOx using an in situ sacrificial Au electrolysis procedure. The products are characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The gas sensing performance of Au/InZrOx composite nanopowder is studied by depositing a thick powder film on interdigitated electrode structures patterned on SiC substrate to facilitate high temperature operation. The resistivity of the Au/InZrOx layer is the sensor signal, and the sensors could be operated at 500–600 °C, which is a suitable temperature range for engine exhaust measurements. The control sensing measurements reveal that Au/InZrOx composite nanopowder exhibits higher response towards 2–20 % O2 gas as compared to pristine InZrOx nanoparticles. Further studies show that when applied to exhaust gases such as CO and nitric oxide (NO), the response of Au/InZrOx sensors is significantly higher towards NO in this temperature range. Thus, sensor performance characteristics of Au/InZrOx composite nanopowder are promising in terms of their applications in automobile exhaust emission control.

In the present study, gold/surfactant core/shell colloidal nanoparticles with a controlled morphology and chemical composition have been obtained via the so-called sacrificial anode technique, carried out in galvanostatic mode. As synthesized Au-NPs had an average core diameter comprised between 4 and 8 nm, as a function of the electrochemical process experimental conditions. The UV–Vis characterization of gold nanocolloids showed clear spectroscopic size effects, affecting both the position and width of the nanoparticle surface plasmon resonance peak. The nanomaterial surface spectroscopic characterization showed the presence of two chemical states, namely nanostructured Au(0) (its abundance being higher than 90%) and Au(I). Au-NPs were then deposited on the top of a capacitive field effect sensor and subjected to a mild thermal annealing aiming at removing the excess of stabilizing surfactant molecules. Au-NP sensors were tested towards some gases found in automotive gas exhausts. The sensing device showed the largest response towards NOx, and much smaller – if any – responses towards interferent species such as NH3, H2, CO, and hydrocarbons.

Nanomaterials have emerging importance in laser desorption ionization mass spectrometry (LDI–MS) with the ultimate objective being to overcome some of the most important limitations intrinsically related to the use of conventional organic matrices in matrix-assisted (MA) LDI–MS. This review provides a critical overview of the most recent literature on the use of gold nanomaterials as non-conventional desorption ionization promoters in LDI– MS, with particular emphasis on bioanalytical applications. Old seminal papers will also be discussed to provide a timeline of the most significant achievements in the field. Future prospects and research needs are also briefly discussed.

Biosystems integration into an organic field-effect transistor (OFET) structure is achieved by spin coating phospholipid or protein layers between the gate dielectric and the organic semiconductor. An architecture directly interfacing supported biological layers to the OFET channel is proposed and, strikingly, both the electronic properties and the biointerlayer functionality are fully retained. The platform bench tests involved OFETs integrating phospholipids and bacteriorhodopsin exposed to 1–5% anesthetic doses that reveal drug-induced changes in the lipid membrane. This result challenges the current anesthetic action model relying on the so far provided evidence that doses much higher than clinically relevant ones (2.4%) do not alter lipid bilayers’ structure significantly. Furthermore, a streptavidin embedding OFET shows label-free biotin electronic detection at 10 parts-per-trillion concentration level, reaching state-of-the-art fluorescent assay performances. These examples show how the proposed bioelectronic platform, besides resulting in extremely performing biosensors, can open insights into biologically relevant phenomena involving membrane weak interfacial modifications.

A new class of nano-antimicrobials was developed by Ion Beam co-Sputtering of ZnO and polytetrafluoro_ ethylene targets. The resulting nanostructured coatings combine the antimicrobial properties of ZnO nanoparticles with the water repellence and anti-stain characters of the dispersing fluoropolymer (CFx). ZnO-CFx nanocomposites were prepared varying ZnO volume fraction (φ) in the CFx matrix by tuning the sputter- ing deposition parameters. Morphological analysis confirmed the presence of homogenously distributed ZnO nanoclusters in the polymer. ZnO loadings ranging in the 0.05-0.15 interval were explored and the nano-composites were characterized by X-ray Photoelectron Spectroscopy (XPS) to investigate their surface chemical composition. XPS spectra evidenced a high degree of polymer defluorina-tion along with the formation of ZnF2 at increasing φ valu-es. Zn speciation was performed on Zn L3M45M45 Auger signal. Coatings bioactivity was assessed against Escheri-chia coli, Staphylococcus aureus, and Kluyveromyces marxianus. At φ ≥ 0.10, ZnO-CFx composites exhibited appreciable antibacterial activity, irrespective of the target organism.

Escherichia coli (E. coli) is one of the most important foodborne pathogens to the food industry responsible for diseases as bloody diarrhea, hemorrhagic colitis and life-threatening hemolytic–uremic syndrome. For controlling and eliminating E. coli, metal nano- antimicrobials (NAMs) are frequently used as bioactive systems for applications in food treatments. Most NAMs provide controlled release of metal ions, eventually slowing down or completely inhibiting the growth of undesired microorganisms. Nonetheless, their antimicrobial action is not totally unraveled and is strongly dependent on metal properties and environmental conditions. In this work, we propose the use of matrix-assisted laser desorption ionization time-of-flight (MALDI TOF) mass spectrometry as a powerful tool for direct, time efficient, plausible identification of the cell membrane damage in bacterial strains exposed to copper-based antimicrobial agents, such as soluble salts (chosen as simplified AM material) and copper nanoparticles. E. coli ATCC 25922 strain was selected as ‘training bacterium’ to set up some critical experimental parameters (i.e. cell concentration, selection of the MALDI matrix, optimal solvent composition, sample preparation method) for the MS analyses. The resulting procedure was then used to attain both protein and lipid fingerprints from E. coli after exposure to different loadings of Cu salts and NPs. Inter- estingly, bacteria exposed to copper showed over-expression of copper binding proteins and degradation of lipids when treated with soluble salt. These findings were completed with other investigations, such as microbiological experiments.

Research on the nanomaterials containing one or more transition metals is growing tremendously, thanks to the large number of preparation processes available and to the novel applications that can be envisaged in several fields. This review presents an overview of the selected studies in the field of antimicrobial textiles, employing bioactive nanophases of elements/compounds such as silver, copper, or zinc oxide. In addition, the history of use of these antimicrobials and their mechanism of action are shortly reported. Finally, a short description is provided of the deposition/preparation methods, which are being used in the authors ’ labs for the development of the textiles modified by the novel nanoantimicrobials

The aim of the present work was to compare the mucoadhesive and efflux pump P-glycoprotein (P-gp) interacting properties of chitosan (CS)- and glycolchitosan (GCS)-based thiomers and corresponding unmodified parent polymers. For this purpose, the glycol chitosan-N-acetyl-cysteine (GCS-NAC) and glycol chitosan-glutathione (GCS-GSH) thiomers were prepared under simple and mild conditions. Their mucoadhesive characteristics were studied by turbidimetric and zeta potential measurements. The P-gp interacting properties were evaluated measuring the effects of thiolated- and unmodified-polymers on the bidirectional transport (BA/AB) of rhodamine-123 across Caco-2 cells as well as in the calcein-AM and ATPase activity assays. Although all the thiomers and unmodified polymers showed optimal-excellent mucoadhesive properties, the best mucoadhesive performances have been obtained by CS and CS-based thiomers. Moreover, it was found that the pretreatment of Caco-2 cell monolayer with GCS-NAC or GCS restores Rho-123 cell entrance by inhibiting P-gp activity. Hence, GCS-NAC and GCS may constitute new biomaterials useful for improving the bioavailability of P-gp substrates.

In the present contribution Angle Resolved X-ray Photoelectron Spectroscopy (AR-XPS) was proposed as useful tool to address the challenge of probing the near-surface region of bio-active sensors surface. A model bio-functionalized surface was characterized by Parallel AR-XPS and commercially available Thermo Avantage-ARProcess software was used to generate non-destructive concentration depth profiles of protein functionalized silicon oxide substrates. At each step of the functionalization procedure, the surface composition, the overlayer thickness, the in-depth organization and the in-plane homogeneity were evaluated. The critical discussion of the generated profiles highlighted the relevance of the information provided by PAR-XPS technique.

Label-free biosensors are of considerable interest for various clinical and biological applications. In these systems, achieving an optimized receptor immobilization strategy critically influence the sensing performance in terms of specificity, sensitivity, response kinetics and detection limits. However, monitoring the receptor spatial organization and the interfaces composition on a nanometer or sub-nanometer scale is a very hard challenge. In the present contribution Parallel Angle Resolved X-ray Photoelectron Spectroscopy (PAR-XPS) was proposed as useful tool to address the challenge of probing the near-surface region of bio-active sensors surface (1). A model receptor was chosen and a well-established functionalization procedure (2) was systematically characterized by PAR-XPS. Commercially available Thermo Avantage-ARProcess software was used to generate non-destructive concentration depth profiles of protein functionalized silicon oxide substrates. At each step of the functionalization procedure, the surface composition, the over layer thickness, the in-depth organization and the in-plane homogeneity were evaluated. Compared to multi-techniques characterization approaches previously proposed in the literature, the present analytical approach boasted the peculiar advantage of providing, simultaneously, morphological and compositional information from the same data set. The critical discussion of the generated profiles highlighted the relevance of the information provided by PAR-XPS technique.

Abstracts of papers

One- and two-dimensional carbon nanostructures, i.e. carbon nanotubes (CNTs) and graphene possess exceptional physical properties owing to their distinctive structure and atomic arrangement. High electrical conductivity, highly exposed surface area and stability of these carbon nanostructures institute them as the leading choice of nanomaterials for a number of electrical and industrial applications. Besides these carbon nanostructures are extremely sensitive towards minute changes in the surrounding gas atmosphere, i.e. their conductance (or resistance) varies greatly with the adsorption-desorption of gas molecules such as nitrogen oxides (NOx). This article critically reviews the most recent advances in NOx sensors based on one- and two-dimensional carbon nanostructures and nanohybrids as gas sensitive materials. The advantages and limitations of CNT- and graphene-based devices are briefly discussed in the light of recent literature. The potential and future perspectives of these devices are also outlined in this study.

21st century has already seen huge progress in science and technology of small, highly sensitive gas sensors, which can selectively detect environmental toxins like NOx – the oxides of nitrogen – a byproduct of fossil fuel combustion. Into this bargain, public became more health-aware and environmental bodies grew stricter, stimulating analytical and material scientists to find new strategies from material synthesis to fabrication of NOx sensors in order to produce fast and reliable gas detectors. To the scientists, semiconducting metal oxides, owing to their low cost, easy processing, high gas response, good electrical properties and above all tunable structure at the nanoscale, always presented a first-hand choice for sensor fabrication. This article presents an overview of the most recent developments in semiconducting NOx gas sensors based on these metal oxide nanostructures and their applications in vehicle exhaust and environmental monitoring. A strong emphasis is presented on chemiresistor and field effect transistor devices using semiconducting metal oxides as active layers. The performance levels of these NOx sensors are compared to those of other devices as well as other semiconductor materials. Furthermore, keeping in mind the ultimate user demands, limitations of the current sensor technologies and future strategies are discussed

Palladium nanoparticles have been electrochemically supported on zirconium oxide nanostructured powders and all the nanomaterials have been characterized by several analytical techniques. The Pd/ZrO2 nanocatalyst is demonstrated to be a very efficient catalyst in Heck, Ullmann, and Suzuki reactions of aryl halides in water. The catalyst efficiency is attributed to the stabilization of Pd nanophases provided by tetra(alkyl)- ammonium hydroxide, which behaves both as base and PTC (phase transfer catalyst) agent.

A Functional Bio-Interlayer Organic Field-Effect Transistor (FBI-OFET) sensor, embedding a streptavidin protein capturing layer, capable to perform label-free specific electronic detection of biotin at 3 part-per-trillion (mass fraction) or 15 pM, is here proposed. The response shows a logarithmic dependence on the analyte concentration along with a dynamic range spanning over five orders of magnitude. The optimization of the FBI analytical performances is achieved by depositing the capturing layer through a controllable Layer-by-Layer (LbL) assembly, while an easy processable spin-coating deposition is proposed for potential low-cost production of equally highly performing sensors. A Langmuirian adsorption based model allows to rationalize the analyte binding to the capturing layer whose analytical performances are discussed accordingly. The FBI-OFET device is shown to operate also with an antibody interlayer as well as with an ad hoc designed micro-fluidic system. These occurrences, along with the proven extremely high sensitivity and selectivity, open to FBI-OFETs appraisal as a suitable platform for disposable electronic strip-tests for assays in biological fluids requiring very low detection limits.

A plasma enhanced chemical vapor deposition process was proposed to functionalize the P3HT organic semiconductor surface of electrolyte gated organic field effect transistors with hydrophilic coatings bearing –COOH groups. Results demonstrate that the developed plasma process allows to functionalize the P3HT surfaces with carboxyl groups with negligible adverse effect on the bulk properties of P3HT as well as on EGOFET performances.

In this paper a study of Multi Wall Carbon Nanotube films deposited at low temperature by means of a spray technique on different substrates is presented. Nanodispersion of nanotube powder in a non-polar 1,2-dichloroethane solvent was used as starting solution. Electron Microscopy in Scanning and Transmission modes were used in order to verify the morphological properties of the deposited films. Visible light detectors were prepared spraying Multi Wall Carbon Nanotubes on silicon substrates with different layouts. In some detectors the nanotubes were covered by an Indium Tin Oxide (ITO) layer. Electrical measurements, both in dark and under light irradiation, were performed and Current-Voltage characteristics are reported. The Indium Tin Oxide coating effect on the photoconductivity yield is presented and discussed along with device ageing test, resulting in a very good photoconduction and stability over four months.

Palladium nanoparticles have been electrochemically supported on zirconium oxide nanostructured powders and all the nanomaterials have been characterized by several analytical techniques. The Pd/ZrO2 nanocatalyst is demonstrated to be a very efficient catalyst in Heck, Ullmann, and Suzuki reactions of aryl halides in water. The catalyst efficiency is attributed to the stabilization of Pd nanophases provided by tetra(alkyl)- ammonium hydroxide, which behaves both as base and PTC (phase transfer catalyst) agent.

The on–board quantification of exhaust emission from the internal combustion engines is of global concern in order to monitor and control release of toxic gaseous pollutants such as the oxides of nitrogen (NOx). This scenario calls for highly performing, cost–effective and long lasting gas sensors. In this regard, semiconducting metal oxides present the foremost choice of active materials for real–time detection of exhaust gases due to their low cost, good electrical properties, high sensitivity and stability at temperatures as high as >500°C [1]. In this work, we report on the synthesis, analytical characterization, and surface modification of metal oxide nanoparticles (ZnO–, ZrOx, InOx- NPs) for their potential application as semiconductor gas sensors. ZnO is a promising material and one of the earliest oxides studied for gas adsorption [2]. However, owing to its high working temperature and limited selectivity, ZnO did not achieve commercial success. ZrOx and InOx nanomaterials are well known active components of NOx sensors, which have shown some performance limitations –either in selectivity or in response intensity and kinetics-. To overcome these limitations, in recent years semiconductor metal oxides (MO) are being frequently modified by selected inclusions of transition metal nanoparticles, bringing their own surface reactivity characteristics to the hybrid catalyst-MO system [3]. In the present study, MO–NPs are prepared via simple and economical sol–gel methods. The surface of MO–NPs is subsequently modified by electro–chemical decoration of nanoscale gold (nano–Au), performed under surfactant stabilization conditions. Since Au nanoparticles exhibit pronounced selectivity toward NOx gases [4], the nano–Au/MO–NPs hybrids are believed to enhance the sensing properties of MO–NPs such as the selectivity and long–term stability of the nanomaterial. Both the pristine MO–NPs and the composite nano–Au/MO–NPs are calcined at temperatures >500°C to induce stability at the usual operating temperature of gas-sensing experiments and the effect of calcination on nanostructure and morphology is systematically studied. The as–prepared and the calcined nanomaterials are characterized by transmission electron microscopy, scanning electron microscopy, X–ray photoelectron spectroscopy, and X–ray diffraction techniques. The results demonstrate that these nanomaterials are highly stable and even ultrafine gold nanophases retain their morphology and surface chemical speciation upon annealing. The experimental evidences support further application of these composite nano–Au/MO–NPs as active elements in semiconductor NOx gas sensors.

Catalysis by transition-metal nanoparticles has undergone an explosive growth during the past decade. This special issue presents the general trends in the current research in this field, the present situation concerning scope and limitations, as well as the future perspectives. Original contributions are also presented on the applications of nano-catalysts to the green synthesis.

Low density lipoprotein self-assembled layers on gold support, proposed as model for oxidation studies, were subjected to oxidation processes using different oxidative agents: 2,20-Azobis(2methylpropionamidine)dihydrochloride, atmospheric oxygen, and metal-induced oxidation. The freshly prepared and the oxidized layers were characterized by X ray photoelectron spectroscopy (XPS), Fourier-Transformed infrared spectroscopy, and Matrix-Assisted Laser Desorption/Ionization-Time of Flight (MALDI-ToF) mass spectrometry to discriminate the effects of oxidative reagents. Data obtained from FTIR and MALDI spectra proved the lipoperoxide formation subsequent to reactive oxygen species attack and the opportunity to use the model to discriminate between oxidation toxicity.

This work highlights the importance of the hydrophilicity of a catalyst’s active sites on an oxygen reduction reaction (ORR) through an electrochemical and physico-chemical study on catalysts based on nitrogen-modified carbon doped with different metals (Fe, Cu, and a mixture of them). BET, X-ray Powder Diffraction (XRPD), micro-Raman, X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Scanning Transmission Electron Microscopy (STEM), and hydrophilicity measurements were performed. All synthesized catalysts are characterized not only by a porous structure, with the porosity distribution centered in the mesoporosity range, but also by the presence of carbon nanostructures. In iron-doped materials, these nanostructures are bamboo-like structures typical of nitrogen carbon nanotubes, which are better organized, in a larger amount, and longer than those in the copper-doped material. Electrochemical ORR results highlight that the presence of iron and nitrogen carbon nanotubes is beneficial to the electroactivity of these materials, but also that the hydrophilicity of the active site is an important parameter affecting electrocatalytic properties. The most active material contains a mixture of Fe and Cu.

The control of pollutants emission from internal combustion engines is a worldwide issue, in the automotive field. The roadmap for the reduction of vehicle emission limits is driving the academic and industrial interest towards the development of innovative systems integrating novel detection elements and fast feedback circuits and actuators. Based on a tighter control over emissions, and starting from 2014, Euro 6 standards are expected to improve the environmental compatibility of a new generation of vehicles in Europe. This scenario calls for a significant improvement of the sensors technologies for the detection of the main pollutants related to the automotive field, including nitrogen oxides (NOx). In this work, we report on the synthesis and analytical characterization of hybrid nanocomposites containing gold nanoparticles (Au-NPs) and metal oxide nanostructures (MO-NPs, such as zirconium oxide, indium oxide, oxide mixtures, etc.). These species are promising for real-time detection of low levels of NOx species, owing to their low cost, high sensitivity and availability under a variety of stoichiometric and mixing ratios, showing different gas sensing characteristics [1- 2]. Different MO-NPs and mixed MO-NP systems were prepared using a simple but efficient sol-gel method. Subsequently, the nano-oxides were electrodecorated by Au-NPs. Since Au nanophases exhibit pronounced selectivity toward NOx gases [3], the resulting hybrid nanocomposites are expected to improve the nanomaterial sensing performance. All the nanomaterials were characterized using FTIR, XPS, XRD, TEM, and SEM techniques. Experimental evidences support further application of these NPs as active elements in novel NOx sensors.

Biological agents play an important role in the deterioration of cultural heritage causing aesthetic, biogeophysical and biogeochemical damages. Conservation is based on the use of preventive and remedial methods. The former aims at inhibiting biological attack, and the latter aims at eradicating the biological agents responsible for biodeterioration. Here, we propose the preparation and the analytical characterisation of copper-based nanocoating, capable of acting both as a remedy and to prevent microbial proliferation. Core–shell CuNPs are mixed with a siliconbased product, commonly used as a water-repellent/consolidant, to obtain a combined bioactive system to be applied on stone substrates. The resulting coatings exert a marked biological activity over a long period of time due to the continuous and controlled release of copper ions acting as biocides. To the best of our knowledge, this is the first time that a multifunctional material is proposed, combining the antimicrobial properties of nanostructured coatings with those of the formulations applied to the restoration of stone artworks. A complete characterisation based on a multitechnique analytical approach is presented.

The aim of this study was to evaluate the performance of chitosan (CS) and glycol chitosan (GCS) nanoparticles containing the surfactant Lipoid S100 for the systemic delivery of low molecular weight heparin (LMWH) upon pulmonary administration. These nanoparticles were prepared in acidic and neutral conditions using the ionotropic gelation technique. The size and zeta potential of the NPs were affected by the pH and also the type of polysaccharide (CS or GCS). The size (between 156 and 385 nm) was smaller and the zeta potential (from +11 mV to +30 mV) higher for CS nanoparticles prepared in acidic conditions. The encapsulation efficiency of LMWH varied between 100% and 43% for the nanoparticles obtained in acidic and neutral conditions, respectively. X-ray photoelectron spectroscopy studies indicated that the surfactant Lipoid S100 was localized on the nanoparticle's surface irrespective of the formulation conditions. In vivo studies showed that systems prepared in acidic conditions did not increase coagulation times when administered to mice by the pulmonary route. In contrast, Lipoid S100-LMWH GCS NPs prepared in neutral conditions showed a pharmacological efficacy. Overall, these results illustrate some promising features of CS-based nanocarriers for pulmonary delivery of LMWH.

Metal nanomaterials have emerging role in surface-assisted laser desorption ionisation–mass spectrometry (SALDI-MS) providing a useful tool to overcome some limitations intrinsically related to the use of conventional organic matrices in matrix-assisted LDI-MS. In this contribution, the possibility to use a stainless steel-supported gold nanoparticle (AuNP) film as a versatile platform for SALDI-MS was assessed. Sacrificial anode electrosynthetic route was chosen in order to obtain morphologically controlled core–shell AuNPs; the colloidal AuNPs were, thereafter, drop cast onto a stainless steel sample plate and the resulting AuNP film was thermally annealed in order to improve its effectiveness as LDI-MS promoter. Spectroscopic characterization of the nanostructured film by X-ray photoelectron spectroscopy was crucial for understanding how annealing induced changes in the surface chemistry and influenced the performance of AuNPs as desorption/ionisation promoter. In particular, it was demonstrated that the post-deposition treatments were essential to enhance the AuNP core/analyte interaction, thus resulting in SALDI-MS spectra of significantly improved quality. The AuNP films were applied to the detection of three different classes of low molecular weight (LMW) analytes, i.e. amino acids, peptides and LMW polymers, in order to demonstrate the versatility of this nanostructured material.

The detailed action mechanism of volatile general anesthetics is still unknown despite their effect has been clinically exploited for more than a century. Long ago it was also assessed that the potency of an anesthetic molecule well correlates with its lipophilicity and phospholipids were eventually identified as mediators. As yet,the direct effect of volatile anesthetics at physiological relevant concentrations on membranes is still under scrutiny. Organic field-effect transistors(OFETs)integrating a phospholipid (PL) functional biointer-layer(FBI)are here proposed for the electronic detection of archetypal volatile anesthetic molecules such as diethylether and halothane. This technology allows to directly interface a PL layer to an electronic transistor channel,and directly probe subtle changes occurring in the bio-layer. Repeatable responses of PLFBI-OFET to anesthetics are produced in a concentration range that reaches few percent,namely the clinically relevant regime. The PLFBI-OFET is also shown to deliver a comparably weaker response to a non-anesthetic volatile molecule such as acetone

Chitosan- and glycol-chitosan thiol conjugates have been developed, in order to realize nanocarriers which can be useful in the transmucosal drug delivery. The aim of the study is to compare the mucoadhesive properties of the two classes of conjugates. Indeed, the presence of thiol groups on the polymer surface is expected both to increase the interaction with the mucin and to promote the absorption of the delivered drugs. Glutathione and N-acetylcysteine have been chosen to synthesize new thiol-derivatives of glycol chitosan to be compared to the analogous chitosan derivatives (1) in terms of mucoadhesion properties. All the conjugates have been formulated as promising nanoparticles (NPs) for drug delivery. In the present contribution, x-ray photoelectron spectroscopy has been performed to analyze the surface chemical composition of both the synthesized polymers and the resulting NPs. The preliminary investigations showed the presence of sulphur on the NPs outer shell thus encouraging the eventual surface mucoadhesive properties of the nanocarriers. Further work is in progress to localize the in-depth distribution (2), once the nanocarriers have been loaded with a model drug.

Transistore comprendente almeno uno strato conduttivo (4), almeno uno strato dielettrico di gate (3) e almeno un film semiconduttore (1) depositato su uno strato di molecola recettore (2) precedentemente depositato o collegato in modo covalente alla superficie del gate dielettrico (3). Detto strato di materiale biologico è costituito da strati singoli o doppi di fosfolipidi, strati costituiti da proteine ​​quali recettori, anticorpi, canali ionici ed enzimi, singoli o doppi strati di fosfolipidi con inclusione o ancoraggio di proteine ​​quali: recettori, anticorpi, ionici canali ed enzimi, strati fatti di sonde oligonucleotidiche (DNA, RNA, PNA), strati fatti di cellule o virus, strati fatti di recettori sintetici per esempio molecole o macromolecole simili ai recettori biologici per proprietà, reattività o aspetti sterici.

Si tratta di un sensore a transistore, cos’ come del suo array, capace di rivelare, in modo affidabile, selettivo e label-free fino ad una singola molecola di DNA così come di anticorpi e peptidi. noltre il semiconduttore usato è un composito nanostrutturato a base di un polimero semiconduttore, facile da preparare, scalabile ed economico, è anche particolarmente stabile quando impiegato in diretto contatto con l’acqua.

Nanoparticles having a core formed of a metal selected from Ag, Cu, Sn and Zn and a shell formed of a plurality of molecules of quaternary ammonium compounds NR 1 R 2 R 3 R 4 + X - , where X is selected from Cl, Br and I and where NR 1 R 2 R 3 R 4 + is a quaternary ammonium compound wherein at least one R is different from the others and is an alkyl chain, linear or functionalised or provided with branches or aromatic lateral groups with length preferably between 8 and 18 atoms of carbon.

In nanoparticles having formula (Me)(NR 4 + X - ) n wherein Me is the metal core selected from Ag, Cu, Sn and Zn; (NR 4 + X - ) is the shell, where X is selected from Cl, Br and I, and R is an alkyl chain C 4 -C 12 , the length of the alkyl chain is chosen to control the release speed of metal ions from the core; several types of nanoparticles all with equal chains in the same particle can form a composition for antimicrobial applications to fabrics and the like.

Transistor comprising at least one conductive layer (4), at least one gate dielectric layer (3) and at least one semiconducting film (1) deposited on top of a receptor molecule layer (2) previously deposited or covalently linked to the surface of the gate dielectric (3). Said layer of biological material is constituted by single or double layers of phospholipids, layers made of proteins such as receptors, antibodies, ionic channels and enzymes, single or double layers of phospholipids with inclusion or anchoring of proteins such as: receptors, antibodies, ionic channels and enzymes, layers made of oligonucleotide (DNA, RNA, PNA) probes, layers made of cells or viruses, layers made of synthetic receptors for example molecules or macromolecules similar to biological receptors for properties, reactivity or steric aspects.

Transistor comprising at least one conductive layer, at least one dielectric layer and at least one thin organic semiconductor film and characterized by at least one layer of biological material deposited directly on the surface of the dielectric. Said layer of biological material is constituted by single or double layers of phospholipids, layers made of proteins such as receptors, antibodies, ionic channels and enzymes, single or double layers of phospholipids with inclusion or anchoring of proteins such as: receptors, antibodies, ionic channels and enzymes, layers made of oligonucleotide (DNA, RNA, PNA) probes, layers made of cells or viruses, layers made of synthetic receptors for example molecules or macromolecules similar to biological receptors for properties, reactivity or steric aspects.