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The role of polymer side chains in conferring selectivity to a sensing organic thin-film transistor is investigated. The responses of both polymer-based transistor and quartz crystal microbalance sensors are evaluated and compared.

Electrolyte gated thin film transistors (TFTs) based on sol–gel processed zinc oxide (ZnO) are investigated using imidazolium-based ionic liquids (ILs), namely [bmim][BF4] and [bmim][PF6], as electrolytes. The capacitance of the ILs is determined by means of electrochemical impedance spectroscopy. The frequency dependence of the capacitance measurements indicates that the electric double layers (EDLs) form below 1 kHz. Impedance measurements are also acquired at different gate voltages and the effect of the bias is discussed in detail. The experimental data suggest that the double layer capacitance of the two ILs depends on the polarization voltage. In terms of transistor characteristics, minimum hysteresis is observed in the case of [bmim][BF4]. Being smaller in size out of the two, a higher ionic mobility is expected. Therefore, faster formation of the EDL can account for suppressed hysteresis in the I–V characteristics. The estimated capacitance was 1.17 μF cm−2 for [bmim][PF6] and 4.05 μF cm−2 for [bmim][BF4], which resulted in a TFT field-effect mobility as high as 6.0 and 1.4 cm2 V−1 s−1, respectively. Also the on–off ratio of the EG-TFT is particularly high, being 104. Moreover, transient current measurements showed that the two ILs behave differently under continuous bias stress. The effect of the metal gate electrode on the device characteristics is also investigated. Five metals of varying work functions are employed for establishing a gate/IL interface. The data do not support that there is a correlation between the threshold voltage and the work function of the metals. On the other hand, the capacitance seems to be more susceptible to changes of the metal gate. [ABSTRACT FROM AUTHOR]

In this article is proposed a new preparation method for composite ultra-thin films for photovoltaic application. Compounds such as Kesterites (CZTS, ternary and quaternary copper and zinc sulfides) could be used in virtue of their semiconductor behavior in conjunction with electrodeposition from aqueous media methodologies; in particular E-ALD (Electrochemical Atomic Layer Deposition) method seems a legitimate alternative to the high pressure and temperature methods used since today. We studied the feasibility of the electrodeposition process of two layers of semiconductors (CuxZnyS, with p electronic proprieties, and CdS with n electronic proprieties), one above the other, by means of E-ALD. Preliminary electrochemical studies revealed the complex nature of the composite film, impairing the anodic stripping of Cd. In order to confirm that the Cd electrodeposition is surface limited, two sets of samples were compared using different conventional and charge controlled potentiostatic electrodeposition methodologies. SEM and XPS characterization was then performed to characterize morphologically and quantitatively the samples. Consequently, the conditions for the surface limited deposition of Cd over CuxZnyS have been reckoned through the electrochemical and spectroscopical analysis. The layered (p-n) structure of the thin film has been confirmed. [ABSTRACT FROM AUTHOR]

Colloids of antimicrobial metal and metal oxide nanoparticles (NPs) were electrochemically prepared and then used as surface modifiers for industrial batches of textiles. Different surface loadings could be easily deposited on the surface of the products of interest in order to inhibit the growth of microbes such as bacteria. Surface chemical characterization was performed using X-ray Photoelectron Spectroscopy technique to quantitatively assess the materials' surface chemical composition. Moreover, the NP chemical speciation was evaluated and correlated to the electrosynthesis characteristics, processing conditions, and textiles storage time. Atomic absorption spectroscopy was employed to quantify the metal ions release in a proper contact solution in order to correlate the surface and bulk availability of NPs with the antimicrobial efficacy. Promising spectroscopic results strongly support future real-life applications in different fields. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the present study, Au-surfactant core-shell colloidal nanoparticles (NPs) with controlled dimension and composition were synthesized by sacrificial anode electrolysis. Transmission electron microscopy (TEM) revealed that Au NPs core diameter is between 8 and 12 nm, as a function of the electrosynthesis conditions. Moreover, surface spectroscopic characterization by X-ray photoelectron spectroscopy (XPS) analysis confirmed the presence of nanosized gold phase. Controlled amounts of Au NPs were then deposited electrophoretically on carbon nanotube (CNT) networked films. The resulting hybrid materials were morphologically and chemically characterized using TEM, SEM (scanning electron microscopy) and XPS analyses, which revealed the presence of nanoscale gold, and its successful deposition on CNTs. Au NP/CNT networked films were tested as active layers in a two-pole resistive NO2 sensor for sub-ppm detection in the temperature range of 100-200 °C. Au NP/CNT exhibited a p-type response with a decrease in the electrical resistance upon exposure to oxidizing NO2 gas and an increase in resistance upon exposure to reducing gases (e.g. NH3). It was also demonstrated that the sensitivity of the Au NP/CNT-based sensors depends on Au loading; therefore, the impact of the Au loading on gas sensing performance was investigated as a function of the working temperature, gas concentration and interfering gases. [ABSTRACT FROM AUTHOR]

Abstract: A two-step bottom up preparation protocol is proposed as a useful tool for the controlled modification of tin oxide films by means of Pd nanoparticles (PdNPs). Colloidal palladium is prepared via an electrolytic process that affords for a core-shell particle structure, while nanostructured tin oxide films are prepared following a sol–gel process. Pd/SnO x composite layers are obtained adding a proper aliquot of pre-formed PdNPs to the tin oxide precursor solution. The nanomaterials surface chemical composition is addressed by X-ray Photoelectron Spectroscopy. Preliminary results on the application of Pd/SnO x as active layers in chemiresistor-type gas-sensing devices are reported, as well. [Copyright &y& Elsevier]

Abstract: A solution processable decyl alkyl chain functionalised 9,10-ter-anthryleneethynylene (D 3A ) amorphous organic semiconductor, endowed with good stability in air, has been investigated as NO x OTFT sensor. The D 3A OTFT operated at room temperature exhibited differential sensitivity to NO and NO2. NO2 detection down to 250ppb could be achieved with very low cross sensitivity to interfering species such as carbon monoxide and hydrogen sulphide. [Copyright &y& Elsevier]

This study demonstrates a simple approach to synthesize green Cu particles stabilized by poly(n-vinyl)pyrrolidone (PVP): the latter acts as stabilizer and dispersant, and its presence in solution eliminates the need for an inert atmosphere. Synthetic parameters were tuned to obtain particles with diameters >200 nm, to be human-safe and prevent nano-cytotoxicity. PVP and reductant concentrations, with reaction times, were varied to investigate their effect on colloidal stability, kinetics, and particles size. Particles were fully characterized, morphologically and spectroscopically. Cu@PVP colloids were washed, to remove unbound PVP and reactions byproducts, and then embedded in chitosan (CS) polymer matrix, to prepare self-standing films for food packaging applications. Films were obtained by a simple solvent evaporation protocol. Pellicles were characterized by common analytical techniques; viscoelastic properties, water uptake, and Cu 2+ ionic release were investigated, as well. The films antimicrobial efficacy was also tested against three different model fungi responsible for agrifood spoilage., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Danilo d'Agostino, Maria Chiara Sportelli, Luigi Gentile, Marika Desopo, Margherita Izzi, Ornella Incerti, Simona Marianna Sanzani, and Nicola Cioffi report financial support was provided by Italian Ministry of Agriculture, Food Sovereignty and Forests. Ornella Incerti reports financial support was provided by Italian Ministry of University and Research. Margherita Izzi, Luigi Gentile, and Nicola Cioffi report financial support was provided by Italian Ministry of University and Research. Maria Chiara Sportelli reports financial support was provided by Fondo Sociale Europeo - Research for Innovation (REFIN). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Aims: We aim to address the knowledge gap surrounding food insecurity in general practice in Norway, focusing on its prevalence among patients, sociodemographic correlates and its relationship with chronic diseases across different age groups., Methods: This study is cross-sectional, collecting data through 69 general practice clinics in 2022 from patients >18 years old visiting their general practitioner. They answered an anonymous questionnaire with the Cornell-Radimer hunger scale. Questions addressed hunger, concerns about food access, financial difficulties purchasing food, impact on children, patient demographics, children, and use of medications for chronic disease. We present logistic regression models with odds ratios (ORs) with 95% confidence intervals to examine associations between food insecurity and patient characteristics., Results: Among 2571 invited patients, 81.2% ( n =2089) participated in the study. Of the participants, 40.1% were considered food insecure. The questions in the Cornell-Radimer hunger scale indicated that most had a mild degree of food insecurity. Food insecurity ranged from 28.9% among those >70 years old to 68.0% among those <30 years old. Food insecurity was associated with age <30 years, being migrant, inversely associated with higher educational levels (OR 0.60, 0.41-0.87) or having own children (OR 0.24, 0.18-0.31). Food insecurity was higher among participants using medications for chronic disease (OR 1.33, 1.05-1.68)., Conclusions: This study underscores the presence of food insecurity in high-income countries like Norway, particularly among specific groups such as young adults, migrants and patients with chronic diseases. These categories of patient could benefit from screening of food insecurity during medical contact., Competing Interests: Declaration of conflicting interestsThe authors have no conflicts of interest to declare.

Our society largely relies on inorganic semiconductor devices which are, so far, fabricated using expensive and complex processes requiring ultra-high vacuum equipment. Here we report on the possibility of growing a p-n junction taking advantage of electrochemical processes based on the use of aqueous solutions. The growth of the junction has been carried out using the Electrochemical Atomic Layer Deposition (E-ALD) technique, which allowed to sequentially deposit two different semiconductors, CdS and Cu 2 S, on an Ag(111) substrate, in a single procedure. The growth process was monitored in situ by Surface X-Ray Diffraction (SXRD) and resulted in the fabrication of a thin double-layer structure with a high degree of crystallographic order and a well-defined interface. The high-performance electrical characteristics of the device were analysed ex-situ and show the characteristic feature of a diode., (© 2024 Wiley-VCH GmbH.)

In this work, we demonstrate that a simple argentometric titration is a scalable, fast, green and robust approach for producing AgCl/antibiotic hybrid antimicrobial materials. We titrated AgNO 3 into tetracycline hydrochloride (TCH) aqueous solution, thus forming AgCl/TCH in a one-step procedure. Furthermore, we investigated the one-pot synthesis of triply synergistic super-nanoantimicrobials, combining an inorganic source of Ag + ions (AgCl), a disinfecting agent (benzyl-dimethyl-hexadecyl-ammonium chloride, BAC) and a molecular antibiotic (tetracycline hydrochloride, TCH). Conventional antimicrobial tests, industrial biofilm detection protocols, and in situ IR-ATR microbial biofilm monitoring, have been adapted to understand the performance of the synthesized super-nanoantimicrobial. The resulting hybrid AgCl/BAC/TCH nanoantimicrobials are found to be synergistically active in eradicating Salmonella enterica and Lentilactobacillus parabuchneri bacteria and biofilms. This study paves the way for the development of a new class of super-efficient nanoantimicrobials that combine relatively low amounts of multiple active species into a single (nano)formulation, thus preventing the development of antimicrobial resistance towards a single active principle., (© 2024. The Author(s).)

This study explores how a simple argentometric titration-like approach could be evolved into a versatile, scalable, fast, and robust strategy for the production of AgCl/quaternary ammonium compounds (QACs) colloidal nanoantimicrobials (NAMs). These systems, which are green, stable, cost-effective, and reproducible are found to be effective against a wide range of food pathogenic bacteria and biofilms. The option of a large-scale production for such colloidal suspensions was explored via the use of a peristaltic pump. The utilization of various types of biosafe QACs and a wide range of solvents including aqueous and organic ones renders this system green and versatile. Nanocolloids (NCs) were characterized using UV-Vis, X-ray photoelectron and Fourier transform infrared (FTIR) spectroscopies. Their morphology and crystalline nature were investigated by transmission electron microscopy (TEM) and selected area diffraction pattern (SAED). Nanoparticle (NP) size distribution and hydrodynamic radius were measured by dynamic light scattering (DLS), while the ζ-potential was found to be highly positive, thus indicating significant colloidal stability and antimicrobial activity. In fact, the higher the NP surface charge, the stronger was their bioactivity. Furthermore, the antibacterial and antibiofilm effects of the as-prepared NCs were tested against Gram-positive bacteria, such as Staphylococcus aureus (ATCC 29213) and Listeria monocytogenes 46 , and Gram-negative bacteria, such as Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853) . The results clearly indicate that AgCl/QACs provide pronounced antibiofilm activity with long-term bacteriostatic effects against foodborne pathogenic bacteria rendering them an ideal choice for active food packaging systems., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Copper nanoparticles (CuNPs) are antimicrobial agents that are increasingly being used in several real-life goods. However, concerns are arising about their potential toxicity and thus, appropriate legislation is being issued in various countries. In vitro exploration of the permeability and the distribution of nanoparticles in cell membranes should be explored as the first step towards the investigation of the toxicity mechanisms of metal nanoantimicrobials. In this work, phosphatidylcholine-based large unilamellar vesicles have been explored as mimics of cellular membranes to investigate the effect of ultra-small CuNPs on the physicochemical features of phospholipid membranes. 4 nm-sized CuNPs were synthesized by a wet-chemical route that involves glutathione as a stabilizer, with further characterization by UV-vis absorption spectroscopy, fluorescence spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. Two fluorescent membrane probes bearing naphthalene moieties (laurdan and prodan) were used to monitor the bilayer structure and dynamics, as well as to demonstrate the strong membranotropic effects of CuNPs. The fluorescence spectroscopic studies were supported by dynamic light scattering (DLS) measurements and the calcein leakage assay. Additionally, the degree of perturbation of the phospholipid bilayer by CuNPs was compared against that of Cu 2+ ions, the latter resulting in negligible effects. The findings suggested that CuNPs are able to damage the phospholipid membranes, leading to their agglomeration or disruption., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This study demonstrates a simple and reproducible approach to synthesize green core-shell copper sub-microparticles stabilized by poly(n-vinyl)pyrrolidone (PVP). Cu@PVP colloids were here prepared using copper sulfate pentahydrate as precursor and glucose as reducing agent. The presence of PVP in the synthetic medium eliminates the need for an inert atmosphere during the process, thus simplifying the whole method. Both the morphology and the spectroscopic properties of Cu@PVP colloids were investigated by transmission electron microscopy, and infrared, UV-Vis and X-ray photoelectron spectroscopies. Size distributions and average shell thickness were obtained by statistical analysis on TEM micrographs, and spectroscopies demonstrated the formation of a PVP layer around the copper core. The produced colloids were employed in composite thin films for potential antimicrobial application, in association with a highly-recyclable polymer: polycarbonate (4,4'-(1-methylethylidene)bis(phenol))., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

We have already formulated solid lipid nanoparticles (SLNs) in which the combination of the neurotransmitter dopamine (DA) and the antioxidant grape-seed-derived proanthocyanidins (grape seed extract, GSE) was supposed to be favorable for Parkinson's disease (PD) treatment. In fact, GSE supply would reduce the PD-related oxidative stress in a synergic effect with DA. Herein, two different methods of DA/GSE loading were studied, namely, coadministration in the aqueous phase of DA and GSE, and the other approach consisting of a physical adsorption of GSE onto preformed DA containing SLNs. Mean diameter of DA coencapsulating GSE SLNs was 187 ± 4 nm vs. 287 ± 15 nm of GSE adsorbing DA-SLNs. TEM microphotographs evidenced low-contrast spheroidal particles, irrespective of the SLN type. Moreover, Franz diffusion cell experiments confirmed the permeation of DA from both SLNs through the porcine nasal mucosa. Furthermore, fluorescent SLNs also underwent cell-uptake studies by using flow cytometry in olfactory ensheathing cells and neuronal SH-SY5Y cells, evidencing higher uptake when GSE was coencapsulated rather than adsorbed onto the particles.

One of the crucial challenges of our time is to effectively use metal and metal oxide nanoparticles (NPs) as an alternative way to combat drug-resistant infections. Metal and metal oxide NPs such as Ag, Ag 2 O, Cu, Cu 2 O, CuO, and ZnO have found their way against antimicrobial resistance. However, they also suffer from several limitations ranging from toxicity issues to resistance mechanisms by complex structures of bacterial communities, so-called biofilms. In this regard, scientists are urgently looking for convenient approaches to develop heterostructure synergistic nanocomposites which could overcome toxicity issues, enhance antimicrobial activity, improve thermal and mechanical stability, and increase shelf life. These nanocomposites provide a controlled release of bioactive substances into the surrounding medium, are cost effective, reproducible, and scalable for real life applications such as food additives, nanoantimicrobial coating in food technology, food preservation, optical limiters, the bio medical field, and wastewater treatment application. Naturally abundant and non-toxic Montmorillonite (MMT) is a novel support to accommodate NPs, due to its negative surface charge and control release of NPs and ions. At the time of this review, around 250 articles have been published focusing on the incorporation of Ag-, Cu-, and ZnO-based NPs into MMT support and thus furthering their introduction into polymer matrix composites dominantly used for antimicrobial application. Therefore, it is highly relevant to report a comprehensive review of Ag-, Cu-, and ZnO-modified MMT. This review provides a comprehensive overview of MMT-based nanoantimicrobials, particularly dealing with preparation methods, materials characterization, and mechanisms of action, antimicrobial activity on different bacterial strains, real life applications, and environmental and toxicity issues.