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The removal of pollutants, such as heavy metals, aromatic compounds, dyes, pesticides and pharmaceuticals, from water is still an open challenge. Many methods have been developed and exploited for the purification of water from contaminants, including photocatalytic degradation, biological treatment, adsorption and chemical precipitation. Absorption-based techniques are still considered among the most efficient and commonly used approaches thanks to their operational simplicity. In recent years, polydopamine-coated magnetic nanoparticles have emerged for the uptake of heavy metals in water treatment, since they combine specific affinity towards pollutants and magnetic separation capacity. In this context, this work focuses on the synthesis of polydopamine (PDA)-coated Super Paramagnetic Iron Oxide Nanoparticles (PDA@SPIONs) as adsorbents for Cu2+ ions, designed to serve as functional nanostructures for the removal of Cu2+ from water by applying a magnetic field. The synthetic parameters, including the amount of SPIONs and PDA, were thoroughly investigated to define their effects on the nanostructure features and properties. Subsequently, the ability of the magnetic nanostructures to bind metal ions was assessed on Cu2+-containing solutions. A systematic investigation of the prepared functional nanostructures was carried out by means of complementary spectroscopic, morphological and magnetic techniques. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) measurements were performed in order to estimate the Cu2+ binding ability. The overall results indicate that these nanostructures hold great promise for future bioremediation applications.

Carbon nanotube polymeric composites are widely developed as piezoresistive sensors. Despite these materials showed improved mechanical stability, they are less sensible than carbon aerogel. Moreover, the piezoresistive properties of these nanocomposites cannot be tuned to adapt the sensor to the different applications. Here we observed as modifying solvent dilution in the hard template synthetic route, allow for the fabrication of porous piezoresistive nanocomposites with different limits of detection, working ranges and sensitivities. More in details three different foams with diverse features were produced. Although all the three materials presented outstanding performances, the porous material prepared at higher dilution showed an incredible limit of detection for displacement (-50 nm) and pressure (0.2 Pa) that are respectively 2.6 and 10 times lower than that recorded at lower prepolymer dilutions. However lower dilutions allow to produce sensors able to monitor larger pressures ranges (up to-150 kPa), which are 3 times higher than that of recorded in composites prepared at higher dilutions. Moreover, all the materials evidenced fast response time and high mechanical and electronics stability. Therefore, we demonstrated as this approach easily allows the synthesis of nanocomposites with improved performances and different sensing properties that can be tuned depending on the needed application with an unprecedent flexibility.

In spite of the weak evidence, antibiotic prophylaxis prior to endoscopic ultrasound-guided fine-needle aspiration of pancreatic cystic lesions is routinely used in the clinical practice. To compare a group of patients treated with antibiotics before fine-needle aspiration of pancreatic cystic lesions and a group who did not undergo antimicrobial prophylaxis. Out of 335 patients with suspected pancreatic cystic lesions referred to our center between 2006 and 2018, after propensity score matching two groups were compared: 135 subjects who underwent endoscopic ultrasound fine-needle aspiration under antibiotic prophylaxis and 135 treated with no antimicrobial agents. Primary outcome was infection rate; secondary endpoints included other complications or antibiotic-related adverse events. Median age was 64 (interquartile range 61–68) and median cyst size was 24 mm (22–28), with no difference between groups. Overall, 10 adverse events (7.1%) of which 2 serious (1.4%) were observed in the antibiotic group and 8 (5.8%) of which 1 (0.7%) serious in the non-antibiotic group. Cyst infection was observed in 2 patients (1.4%) in the antibiotic group and 3 patients (2.2%) in the other cohort (p = 0.65). Prophylactic antibiotics do not seem to substantially reduce this risk of infection, and their routine use should be abandoned.

Hypothesis Nanocarbon/polymeric 3D porous composites have been widely developed as piezoresistive sensors due to their improved performances. Functionalized nanocarbon is usually used to allow its adsorption on the surface of porous polymeric material. However, both the functionalization and the surface localized distribution of the nanomaterial can limit the nanocarbon effect on conductivity and mechanical stability of the material thus affecting piezoresistive performances. Experiments A novel nanoarchitectonics strategy to prepare an elastomeric/carbon nanotubes (CNTs) 3D porous piezoresistive nanocomposite is developed. The fabrication route does not require complex apparatus and CNTs chemical functionalization. Moreover, foams of any shape and dimensions can be produced with neither complex machinery and procedures nor wastes production. Findings The obtained material is characterized by the presence of well dispersed pristine CNTs on both surface and bulk of the polymeric matrix. The foam exhibited improved piezoresistive properties with excellent compressive stress (>150 kPa), sensitivity at low displacement (29 kPa−1) and limit of detection for both pressure (2 Pa) and extension (130 nm). These excellent features could allow the use of the as prepared nanocomposite in different applications ranging from wearable devices to robotic or infrastructure monitoring with outstanding flexibility.

Sulfamethoxazole (SMX) is a commonly used antibiotic which accumulation can favor the development of antimicrobial resistance. Therefore, easy and cheap system to monitor the presence of SMX are needed for human health protection. Herein we present a straightforward all electrochemical approach to fabricate a sensor based on a nanocomposite molecularly imprinted polymer (nanoMIP) for the determination of SMX. Firstly, oxidized multiwalled carbon nanotubes (oxMWCNTs) were electrochemically deposited on a polarized electrode to increase electrodic surface area up to 350%. Then, ultrathin overoxidized polypyrrole MIP in presence of SMX was electropolymerized on oxMWCNTs surface (nanoMIP). Finally, antibiotic was electrochemically removed. The obtained nanoMIP was characterized by atomic force microscopy, X-ray photoelectron spectroscopy and electrochemical techniques. The nanoMIP was used for the electrochemical detection of SMX evidencing a lower limit of detection (413 nM) and a wider linear range (1.99–10.88 μM) with respect a non-nanostructured film. The nanoMIP evidenced also good affinity and a highly reproducible response (RSD = 1.2%). The sensor was able to determine SMX in milk samples evidencing good recovery values. The proposed approach can be also used in future to easily prepare different nanoMIP based sensors with improved performances for different target molecules thus overcoming current fabrication limits.

In spite of promising preliminary results, evidence supporting the use of non-anesthesiologist-administered propofol sedation (NAAP) in endoscopic ultrasound (EUS) procedures is still limited. The aim of this manuscript was to examine the safety and efficacy of NAAP as compared to anesthesiologist-administered propofol sedation in EUS procedures performed in a referral center. Out of 832 patients referred to our center between 2016 and 2019, after propensity score matching two groups were compared: 305 treated with NAAP and 305 controls who underwent anesthesiologist-administered propofol sedation. The primary outcome was the rate of major complications. The median age was 67 years and the proportion of patients with comorbidities was 31.8% in both groups. One patient in each group (0.3%) experienced a major complication, whereas minor complications were observed in 13 patients in the NAAP group (4.2%) and 10 patients in the control group (3.2%; p = 0.52). Overall pain during the procedure was 2.3 ± 1 in group 1 and 1.8 ± 1 in group 2 (p = 0.67), whereas pain/discomfort upon awakening was rated as 1 ± 0.5 in both groups (p = 0.72). NAAP is safe and effective even in advanced EUS procedures. Further randomized-controlled trials (RCTs) are warranted to confirm these findings.

BACKGROUND AND AIM Observational studies showed significant liver stiffness regression after sustained virological response, but long-term effects of antiviral therapy are still unknown. The aim of this study was to assess the magnitude of change in stiffness up to 5 years after therapy in hepatitis C patients undergoing antiviral treatment. METHODS Data of 153 patients were retrieved. Stiffness was assessed by Fibroscan at baseline, end of treatment, 6 months after treatment, and every year hereafter up to 5 years. RESULTS Seventy patients were treated with interferon-based regimens and 83 with direct antiviral agents. Baseline cirrhosis was diagnosed in 53 (34.6%) patients. Sustained virological response was achieved in 112 patients, whereas 41 were non-responders. In responders, stiffness decreased from 12.3 kPa (9-17.8) to 6.6 kPa (5.3-7.4) at 5 years. A sharper decline was observed immediately after treatment (-2.5 kPa at the end of treatment and -3.7 kPa at 6 months), while from 1 year onwards, the magnitude of stiffness decrease was progressively lower. In non-responders, stiffness showed a slight decrease at the end of treatment (from 19.2 to 18.1 kPa), then returned to baseline levels at 6 months (19.4 kPa), and finally increased over time up to 23.7 kPa (15-32.5) at 5 years. The proportion of cirrhotic patients decreased by 50% at 6 months and finally fell

A method for the aqueous synthesis of stable and biocompatible citrate-coated palladium nanoparticles (PdNPs) in the size range comparable to natural enzymes (4&ndash, 8 nm) has been developed. The toxicological profile of PdNPs was assessed by different assays on several cell lines demonstrating their safety in vitro also at high particle concentrations. To elucidate their cellular fate upon uptake, the localization of PdNPs was analyzed by Transmission Electron Microscopy (TEM). Moreover, crucial information about their intracellular stability and oxidation state was obtained by Sputtering-Enabled Intracellular X-ray Photoelectron Spectroscopy (SEI-XPS). TEM/XPS results showed significant stability of PdNPs in the cellular environment, an important feature for their biocompatibility and potential for biomedical applications. On the catalytic side, these PdNPs exhibited strong and broad antioxidant activities, being able to mimic the three main antioxidant cellular enzymes, i.e., peroxidase, catalase, and superoxide dismutase. Remarkably, using an experimental model of a human oxidative stress-related disease, we demonstrated the effectiveness of PdNPs as antioxidant nanozymes within the cellular environment, showing that they are able to completely re-establish the physiological Reactive Oxygen Species (ROS) levels in highly compromised intracellular redox conditions.

User-friendly and energy-efficient methods able to work in noncontinuous mode for in situ purification of olive mill wastewater (OMW) are necessary. Herein we determined the potential of oxidized multiwalled carbon nanotubes entrapped in a microporous polymeric matrix of polydimethylsiloxane in the removal and recovery of phenolic compounds (PCs) from OMW. The fabrication of the nanocomposite materials was straightforward and evidenced good adsorption capacity. The adsorption process is influenced by the pH of the OMW. Thermodynamic parameters evidenced the good affinity of the entrapped nanomaterial towards phenols. Furthermore, the kinetics and adsorption isotherms are studied in detail. The presence of oil inside the OMW can speed up the uptake process in batch adsorption experiments with respect to standard aqueous solutions, suggesting a possible use of the nanocomposite for fast processing of OMW directly in the tank where they are stored. Moreover, the prepared nanocomposite is safe and can be easily handled and disposed of, thus avoiding the presence of specialized personnel. After the adsorption process the surface of the nanomaterial can be easily regenerated by mild treatments with diluted acetic acid, thus permitting both the recyclability of the nanomaterial and the recovery of phenolic compounds for a possible use as additives in food and nutraceutical industries and the recovery of OMW for fertirrigation.

Herein we present a straightforward approach for the use of polydopamine (PDA) in adsorption of heavy metals from aqueous solutions. This is achieved by fabricating a healthy and environmentally friendly polydimethylsiloxane (PDMS) foam with a mussel inspired PDA layer deposited on the surface. Critical adsorption parameters (pH, temperature and PDA thickness) are optimized by the application of experimental design methodology. Adsorption kinetics and isotherms are studied in detail evidencing a good fitting with Langmuir isotherm and pseudo-second-order kinetics thus suggesting the occurrence of a chemical sorption process with monolayer nature between metals and PDMS/PDA foam. Intraparticle diffusion model evidences good accessibility and high affinity of binding sites on PDA surface. Once adsorbed, metals are reduced to a lower toxic form and can be then removed by a mild acidic treatment thus being easily collected and stocked.

This paper reports a new method to obtain ultra-small Pd and Pt nanoparticles (0.5–1 nm) supported on multi-walled carbon nanotubes (MWCNTs). Even at high loadings of both metals (22.3 and 31.5% (wt/wt) of Pd2+ and Pt2+, respectively), very narrow and unimodal particle size distributions are achieved. The complexing capabilities of polyethyleneimine covalently attached to the surface of the tubes are optimal for the retention of Pd2+ and Pt2+ from solution. We have addressed the reduction of the retained ions by two approaches: a classical treatment with NaBH4 in aqueous solution, and a novel method using hydrogen cold plasma to preserve the structural features of the material. Cold plasma produced degrees of reduction similar or even larger than NaBH4, supporting the advantage of hydrogen cold plasma as reducing agent as it is a simple, clean and fast (15 minutes) procedure. XPS analysis of the reduced materials show an increase in the electron density near the Fermi level. Pt/MWCNT materials have been tested as anode for methanol electrooxidation, showing a catalytic profile typical of that observed for platinum nanoparticles. The stability after 1000 cycles of the plasma-reduced materials is much larger than these reported for Pt/carbon materials, indicating the stability of the ultra-small nanoparticles.

Oil wastewater and spilled oil have caused serious environmental pollution and damage to public health in the past few years. Therefore, considerable efforts are being made to develop sorbent materials that are able to separate oil from water with high selectivity and sorption capacity. However most of them exhibit low reusability, with low volume absorption capacity and poor mechanical properties. Moreover, their synthesis is time-consuming, complex and expensive, limiting their practical application in the case of an emergency. Here we propose an innovative approach for the fabrication of porous PDMS starting from an inverse water-in-silicone procedure able to selectively collect oil from water in a few seconds. The synthesis is dramatically faster than previous approaches, permitting the fabrication of the material in a few minutes independent of the dimensions of the sponges. The porous material possessed a higher volume sorption capacity with respect to other materials already proposed for oil sorption from water and excellent mechanical and reusability properties. This innovative, fast and simple approach can be successful in the case of an emergency, such as an oil spill accident, permitting in situ fabrication of porous absorbents.

Energy efficient, low-cost, user-friendly, and green methods for the removal of toxic phenolic compounds from aqueous solution are necessary for waste treatment in industrial applications. Herein we present an interesting approach for the utilization of oxidized carbon nanotubes (CNTs) in the removal of phenolic compounds from aqueous solution. Dried pristine CNTs were stably incorporated in a solid porous support of polydimethylsiloxane (PDMS) facilitating the handling during both oxidation process of the nanomaterial and uptake of phenolic compounds, and enabling their safe disposal, avoiding expensive post-treatment processes. The adsorption studies indicated that the materials can efficiently remove phenolic compounds from water with different affinities towards different phenolic compounds. Furthermore, the adsorption kinetics and isotherms were studied in detail. The experimental data of adsorption fitted well with Langmuir and Freundlich isotherms, and pseudo-second-order kinetics, and the results indicated that the adsorption process was controlled by a two-step intraparticle diffusion model. The incorporation of CNTs in polymeric matrices did not affect their functionality in phenol uptake. The material was also successfully used for the removal of phenolic compounds from agricultural waste, suggesting its possible application in the treatment of wastewater. Moreover, the surface of the material could be regenerated, decreasing treatment costs.

The present work describes the development of a novel simple and cheap electrochemical sensor based on molecularly imprinted polydopamine, for the detection of sulfamethoxazole (SMX) an antibiotic widely used in food industry. A double step procedure is used for sensor fabrication consisting in molecularly imprinted polydopamine (PDA-MIP) electropolymerization on a gold electrode and template removal through a simple washing procedure with diluted acetic acid. SMX detection was then performed amperometrically. A deep investigation of PDA-MIP electropolymerization was performed combining electrochemical, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) characterization and comparing the obtained results with the corresponding non-imprinted polymer (PDA-NIP), evidencing, for the first time, the possibility of secondary reaction that can occur between template molecule and polymer during material synthesis. Antifouling properties of here prepared PDA-MIP film were observed avoiding the use of complex cleaning procedure of electrode surface during the measurements. Under the selected optimum conditions, MIP sensor evidenced a linear range from 0.8 to 170 μM and a good selectivity in presence of other structurally related molecules such as sulfadimethoxine. The PDA-MIP film was then used for the first time in food analysis to determine SMX in spiked milk samples at two different concentrations (3.4 μM and 9.8 μM) obtaining satisfactory recovery results (103 ± 6% and 99 ± 8% respectively).

Observational studies showed significant liver stiffness regression after sustained virological response, but long-term effects of antiviral therapy are still unknown. The aim of this study was to assess the magnitude of change in stiffness up to 5 years after therapy in hepatitis C patients undergoing antiviral treatment.Data of 153 patients were retrieved. Stiffness was assessed by Fibroscan at baseline, end of treatment, 6 months after treatment, and every year hereafter up to 5 years.Seventy patients were treated with interferon-based regimens and 83 with direct antiviral agents. Baseline cirrhosis was diagnosed in 53 (34.6%) patients. Sustained virological response was achieved in 112 patients, whereas 41 were non-responders. In responders, stiffness decreased from 12.3 kPa (9-17.8) to 6.6 kPa (5.3-7.4) at 5 years. A sharper decline was observed immediately after treatment (-2.5 kPa at the end of treatment and -3.7 kPa at 6 months), while from 1 year onwards, the magnitude of stiffness decrease was progressively lower. In non-responders, stiffness showed a slight decrease at the end of treatment (from 19.2 to 18.1 kPa), then returned to baseline levels at 6 months (19.4 kPa), and finally increased over time up to 23.7 kPa (15-32.5) at 5 years. The proportion of cirrhotic patients decreased by 50% at 6 months and finally fell 5% at 4 years after treatment.Stiffness declines significantly after achieving response, and the magnitude of decline is greater in the first year after treatment, while it tends to plateau from 1 year onwards.

New developments in nanotechnology are increasingly designed to modulate relevant interactions between nanomaterials and neurons, with the aim of exploiting the physical properties of synthetic materials to tune desired and specific biological processes. Carbon nanotubes have been applied in several areas of nerve tissue engineering to study cell behavior or to instruct the growth and organization of neural networks. Recent reports show that nanotubes can sustain and promote electrical activity in networks of cultured neurons. However, such results are usually limited to carbon nanotube/neuron hybrids formed on a monolayer of dissociated brain cells. In the present work, we used organotypic spinal slices to model multilayer tissue complexity, and we interfaced such spinal segments to carbon nanotube scaffolds for weeks. By immunofluorescence, scanning and transmission electronic microscopy, and atomic force microscopy, we investigated nerve fiber growth when neuronal processes exit the spinal explant and develop in direct contact to the substrate. By single-cell electrophysiology, we investigated the synaptic activity of visually identified ventral interneurons, within the ventral area of the explant, thus synaptically connected, but located remotely, to the substrate/network interface. Here we show that spinal cord explants interfaced for weeks to purified carbon nanotube scaffolds expand more neuronal fibers, characterized by different mechanical properties and displaying higher growth cones activity. On the other hand, exploring spontaneous and evoked synaptic activity unmasks an increase in synaptic efficacy in neurons located at as far as 5 cell layers from the cell-substrate interactions.

A new amperometric, nanostructured sensor for the analytical determination of hydrogen peroxide is proposed. This sensor was constructed by immobilizing silver nanoparticles in a polyvinyl alcohol (PVA) film on a platinum electrode, which was performed by direct drop-casting silver nanoparticles that were capped in a PVA colloidal suspension. UV-vis spectroscopy, X-ray diffraction and transmission electron microscopy were used to give a complete characterization of the nanostructured film. Cyclic voltammetry experiments yielded evidence that silver nanoparticles facilitate hydrogen peroxide reduction, showing excellent catalytic activity. Moreover, the cronoamperometric response of modified sensors was dependent on nanoparticle lifetime. Experiments were performed, using freshly prepared solutions, after 4 and 8 days. Results concerning the quantitative analysis of hydrogen peroxide, in terms of detection limit, linear range, sensitivity and standard deviation (STD), are discussed for each tested sensor type. Utilization of two different linear ranges (40 microM to 6mM and 1.25 microM to 1.0mM) enabled the assessment of concentration intervals having up to three orders of magnitude. Moreover, the electrode made using a 4-day-old solution showed the maximal sensitivity of 128 nA microM(-1)(4090 nA microM(-1)cm(-2)), yielding a limit of detection of 1 microuM and STD of 2.5 microAmM(-1). All of these analytical parameters make the constructed sensors suitable for peroxide determination in aqueous solution.

An amperometric glucose biosensor based on glucose oxidase immobilized in electrosynthesized poly-o-phenylenediamine was successfully applied to the determination of a wide group of heavy metals of environmental interest. The inhibition effects of Hg2+, Ag+, Cu2+, Cd2+, Pb2+, Cr3+, Fe3+, Co2+, Ni2+, Zn2+, Mn2+ and also CrO42− on glucose oxidase were studied. Collected data showed a reversible inhibition mechanism. Results about the quantitative analysis of metal ions in terms of detection limit, linear range, sensitivity and R.S.D. are discussed for each tested metal ion. The biosensor was able to discriminate two different oxidation states of chromium being able to reject Cr3+ and to detect the toxic species CrO42−. Also biosensor storage stability and response reproducibility were investigated. Moreover, this study represents the first attempt of evaluating the effect of the hydrogen peroxide decomposition by metal ions on the response of an enzymatic biosensor based on the amperometric detection of the hydrogen peroxide. Experiments were performed with the aim to quantitatively evaluate, for any single metal ion, if this process is competitive with the inhibition of enzymatic reaction in the adopted experimental conditions.

Electroactive nanoparticles of molecularly imprinted polymers (MIP NPs) specific for a non-electroactive template (i.e., the antibiotic vancomycin) were for the first time synthesized by solid-phase synthesis adding two ferrocene-derivative monomers (namely, vinylferrocene and ferrocenylmethyl methacrylate) in different amount to polymerization mixture. MIP NPs were characterized by dynamic light scattering and by cyclic voltammetry studies. This latter allowed identifying the synthetic conditions determining the highest MIP NP electroactivity. The content of electrochemical label was verified by X-Ray Photoelectron Spectroscopy, which provided an estimation of the amount of ferrocene moieties in nanoparticle structure. In the attempt to apply MIP NPs for sensing applications, nanoparticles were anchored to a Nafion modified electrode by a simple self-assembly process and the indirect electrochemical detection of vancomycin was allowed by the change of ferrocene group redox properties upon the exposure to vancomycin. The observed behavior is believed to be due to hindering of the electron transfer process of the ferrocene redox sites within nanoparticles by their interaction with non-electroactive vancomycin. A novel sensing platform is thus developed by directly anchoring to the electrode surface an electroactive probe integrated within the imprinted polymer thus allowing the selective, easy and rapid electrochemical detection of non-electroactive target molecules.

Myocardial tissue engineering currently represents one of the most realistic strategies for cardiac repair. We have recently discovered the ability of carbon nanotube scaffolds to promote cell division and maturation in cardiomyocytes. Here, we test the hypothesis that carbon nanotube scaffolds promote cardiomyocyte growth and maturation by altering the gene expression program, implementing the cell electrophysiological properties and improving networking and maturation of functional syncytia. In our study, we combine microscopy, biological and electrophysiological methodologies, and calcium imaging, to verify whether neonatal rat ventricular myocytes cultured on substrates of multiwall carbon nanotubes acquire a physiologically more mature phenotype compared to control (gelatin). We show that the carbon nanotube substrate stimulates the induction of a gene expression profile characteristic of terminal differentiation and physiological growth, with a 2-fold increase of α-myosin heavy chain (P < 0.001) and upregulation of sarcoplasmic reticulum Ca(2+) ATPase 2a. In contrast, markers of pathological hypertrophy remain unchanged (β-myosin heavy chain, skeletal α-actin, atrial natriuretic peptide). These modifications are paralleled by an increase of connexin-43 gene expression, gap junctions and functional syncytia. Moreover, carbon nanotubes appear to exert a protective effect against the pathologic stimulus of phenylephrine. Finally, cardiomyocytes on carbon nanotubes demonstrate a more mature electrophysiological phenotype of syncytia and intracellular calcium signaling. Thus, carbon nanotubes interacting with cardiomyocytes have the ability to promote physiological growth and functional maturation. These properties are unique in the current vexing field of tissue engineering, and offer unprecedented perspectives in the development of innovative therapies for cardiac repair.

In this work, we introduce a hybrid atomic-force/near-field scanning microwave microscope, exploiting the tomographic capabilities of the microwave microscopy to explore structures of relevant interest, namely, samples involving both biological and non-biological materials at the same time. In particular, we show imaging of C2C12 muscle cells grown in the presence of bundles of multi-walled carbon nanotubes: here, the microwave microscopy, by virtue of its tomographic potentiality, highlights how cells incorporate some nanotubes in their fibers.

To recreate in vitro 3D neuronal circuits will ultimately increase the relevance of results from cultured to whole-brain networks and will promote enabling technologies for neuro-engineering applications. Here we fabricate novel elastomeric scaffolds able to instruct 3D growth of living primary neurons. Such systems allow investigating the emerging activity, in terms of calcium signals, of small clusters of neurons as a function of the interplay between the 2D or 3D architectures and network dynamics. We report the ability of 3D geometry to improve functional organization and synchronization in small neuronal assemblies. We propose a mathematical modelling of network dynamics that supports such a result. Entrapping carbon nanotubes in the scaffolds remarkably boosted synaptic activity, thus allowing for the first time to exploit nanomaterial/cell interfacing in 3D growth support. Our 3D system represents a simple and reliable construct, able to improve the complexity of current tissue culture models.

One of the most important CPs is polypyrrole (PPy) because of its high stability, electronic conductivity, ion exchange capacity and biocompatibility. To improve the performance or extend the functions of the organic devices, CPs usually have to be nanostructured, in fact they are synthesized in the form of micro/nanotubes In this work electrosynthesized polypyrrole nanostructures prepared by a reported template-free method is investigated, in particular a preliminary analysis of high-resolution spectra, both for nanostructured sample and bulk sample has been performed.

The present work describes the development of a simple and cost-effective electrochemical sensor for sulfadimethoxine (SDM) based on molecularly imprinted overoxidized polypyrrole (PPy). An all electrochemical approach is used for sensor fabrication and application. Several parameters influencing the imprinting effect are discussed and evaluated.

XPS represents a powerful tool for investigation of chemistry involved in chemical sensors, as analytes and recognition elements interact at a device surface, the region analyzed by the spectroscopic technique. In this way, the processes involved in preparation, operation and limiting life of sensors can be unraveled. Application of XPS to (bio)chemical sensors is reviewed with particular attention to electrochemical sensors, which account for more extensive literature. Systems based on polymers, organic mono/multilayers, carbon nanotubes and graphene, metallic species, also in the nanostructure format, and bioreceptors and relevant composites have been considered with a special focus on the information provided by XPS analysis on such (bio)sensing systems, highlighting the role played by XPS in sensor technology and giving at the same time an idea of what is still missing in this field thus advancing possible future uses of XPS in sensing technology.

Oil/water separation is a worldwide challenge to prevent serious environmental pollution. The development of sorbent materials with high selectivity, sorption capacity, easy collection and recyclability is of high demand for spilled oil recovery. In this field, magnetic controllable materials have received wide attention due to the possibility of easily being driven to polluted areas and recovered by simple magnetic interaction. However, most of them exhibited low reusability, low oil uptake ability and low mechanical properties. Moreover, their synthesis is complex and expensive. Here, we propose for the first time the fabrication of a porous reusable magnetic nanocomposite based on polydimethylsiloxane (PDMS) and multiwalled carbon nanotubes (MWNTs) via a low cost approach. The material can selectively collect oil from water reaching equilibrium in less than two minutes, evidencing a higher volume sorption capacity with respect to other already proposed materials for oil sorption from water. Furthermore, the material evidenced excellent mechanical properties with a stress at 60% strain at least 10 times higher with respect to other proposed similar materials and maintained its characteristics after 50 cycles at 90% strain, along with high thermal and chemical stability, making them useful as high-performance systems for plugging oil leakage.

Nucleoside-functionalized multi-walled carbon nanotubes (N-MWCNTs) were synthesized and characterized. A self-organization process using hydrogen bonding interactions was then used for the fabrication of self-assembled N-MWCNTs films free of stabilizing agents, polymers, or surfactants. Membranes were produced by using a simple water-dispersion-based vacuum-filtration method. Hydrogen-bond recognition was confirmed by analysis with IR spectroscopy and TEM images. Restoration of the electronic conduction properties in the N-MWCNTs membranes was performed by removing the organic portion by thermal treatment under an argon atmosphere to give d-N-MWCNTs. Electrical conductivity and thermal gravimetric analysis (TGA) measurements confirmed the efficiency of the annealing process. Finally, oxidative biodegradation of the films N-MWCNTs and d-N-MWCNTs was performed by using horseradish peroxidase (HRP) and low concentrations of H2O2. Our results confirm that functional groups play an important role in the biodegradation of CNT by HRP: N-MWCNTs films were completely biodegraded, whereas for d-N-MWCNTs films no degradation was observed, showing that the pristine CNT undergoes minimal enzyme-catalyzed oxidation This novel methodology offers a straightforward supramolecular strategy for the construction of conductive and biodegradable carbon nanotube films. Conductive and biodegradable films: A self-organization process using hydrogen-bond interactions (see scheme, MWCNT=multiwalled carbon nanotube) is used for the fabrication of conductive and biodegradable carbon nanotube films totally free of stabilizing agents, polymers, or surfactants.

Preliminary results on detection of neurotransmitter serotonin using an electrochemical sensor, based on a composite made of core-shell molecularly imprinted polymer (MIP) nanoparticles and polyeth ...

Nanomaterials interact with cells and modify their function and biology. Manufacturing this ability can provide tissue-engineering scaffolds with nanostructures able to influence tissue growth and performance. Carbon nanotube compatibility with biomolecules motivated ongoing interest in the development of biosensors and devices including such materials. More recently, carbon nanotubes have been applied in several areas of nerve tissue engineering to study cell behavior or to instruct the growth and organization of neural networks. To gather further knowledge on the true potential of future constructs, in particular to assess their immune-modulatory action, we evaluate carbon nanotubes interactions with human dendritic cells (DCs). DCs are professional antigen-presenting cells and their behavior can predict immune responses triggered by adhesion-dependent signaling. Here, we incorporate DC cultures to carbon nanotubes and we show by phenotype, microscopy, and transcriptional analysis that in vitro differentiated and activated DCs show when interfaced to carbon nanotubes a lower immunogenic profile. journal article research support, non-u.s. gov't 2013 2013 11 15 imported

In the last decade, carbon nanotube growth substrates have been used to investigate neurons and neuronal networks formation in vitro when guided by artificial nano-scaled cues. Besides, nanotube-based interfaces are being developed, such as prosthesis for monitoring brain activity. We recently described how carbon nanotube substrates alter the electrophysiological and synaptic responses of hippocampal neurons in culture. This observation highlighted the exceptional ability of this material in interfering with nerve tissue growth. Here we test the hypothesis that carbon nanotube scaffolds promote the development of immature neurons isolated from the neonatal rat spinal cord, and maintained in vitro. To address this issue we performed electrophysiological studies associated to gene expression analysis. Our results indicate that spinal neurons plated on electro-conductive carbon nanotubes show a facilitated development. Spinal neurons anticipate the expression of functional markers of maturation, such as the generation of voltage dependent currents or action potentials. These changes are accompanied by a selective modulation of gene expression, involving neuronal and non-neuronal components. Our microarray experiments suggest that carbon nanotube platforms trigger reparative activities involving microglia, in the absence of reactive gliosis. Hence, future tissue scaffolds blended with conductive nanotubes may be exploited to promote cell differentiation and reparative pathways in neural regeneration strategies. © 2013 Fabbro et al.

Nanoscale manipulations of the extracellular microenvironment are increasingly attracting attention in tissue engineering. Here, combining microscopy, biological, and single-cell electrophysiological methodologies, we demonstrate that neonatal rat ventricular myocytes cultured on substrates of multiwall carbon nanotubes interact with carbon nanotubes by forming tight contacts and show increased viability and proliferation. Furthermore, we observed changes in the electrophysiological properties of cardiomyocytes, suggesting that carbon nanotubes are able to promote cardiomyocyte maturation.

In this work a new original amperometric sensor for H 2 O 2 detection based on a Pt electrode modified with Te-microtubes was developed. Te-microtubes, synthesized by the simple thermal evaporation of Te powder, have a tubular structure with a hexagonal cross-section and are open ended. Modified electrode was prepared by direct drop casting of the mixture of Te-microtubes dispersed in ethanol on Pt surface. The spectroscopic characterization of synthesized Te-microtubes and Pt/Te-microtubes modified electrodes was performed by scanning electron microscopy (SEM), energy-dispersive X-rays microanalysis (EDX), X-ray diffraction analysis (XRD) and X-ray photoelectron spectroscopy (XPS). Moreover a complete electrochemical characterization of the new composite material Pt/Te-microtubes was performed by cyclic voltammetry (CV) and cronoamperometry (CA) in phosphate buffer solution (PBS) at pH 7. Electrochemical experiments showed that the presence of Te-microtubes on modified electrode was responsible for an increment of both cathodic and anodic currents in presence of H 2 O 2 with respect to bare Pt. Specifically, data collected from amperometric experiments at −150 mV vs. SCE in batch and −200 mV vs. SCE in flow injection analysis (FIA) experiments show a remarkable increment of the cathodic current. The electrochemical performances of tested sensors make them suitable for the quantitative determination of H 2 O 2 substrate both in batch and in FIA.

A screen-printed electrode amperometric biosensor based on glucose oxidase was successfully used for the inhibitive detection of a wide set of heavy metal ions (Hg2+, Ag+, Cu2+, Cd2+, Co2+, Ni2+) in a flow-injection system. The present work represents a successful way of combining advantages coming from Flow Injection Analysis (FIA) with ones deriving from the use of screen-printing technology in the development of an enzyme inhibition based biosensor. One of the most novel and attractive features of the developed system is the easy and rapid response recovery that does not require any treatment with regenerating reagents. Moreover, sensor response was satisfactory in terms of linear range, limit of detection (LOD), sensitivity and standard deviation. In particular, Hg2+, Cu2+, Cd2+, Co2+, Ni2+ have been successfully revealed at ppm concentration while LOD for Ag+ is in the ppb range. Also the application of the system in glucose detection was satisfactory. Glucose concentrations in the range 0.5–50 mM were detected and sensor response to glucose 10 mM revealed to be stable for 4 hours analysis after being subject to 20 subsequent injections.