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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.

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.