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Abstract  A novel procedure to synthesize poly(2-Hydroxyethylmethacrylate)-silica blend hybrids is presented. Methacrylate monomers bearing an alkoxysilyl unit, prepared by Michael addition of 2-Hydroxyethylmethacrylate (HEMA) to 3-Aminopropyltriethoxysilane (APTS), were employed. By 13C NMR and mass analysis it was possible to establish the formation of coupling hybrid species. A hybrid material, with final concentration of 30% w/w of silica gel to the mass of polymer, was obtained through basic catalysed sol–gel process of tetraethoxysilane (TEOS) and the alkoxysilyl unit of the hybrid monomer, followed by in situ free-radical polymerization. Optical transparency and higher glass transition temperature than pHEMA suggest an increase in either density or strong interphase interactions. Moreover, pHEMA/SiO2 gel blend hybrid exhibits better thermal stability than the as-prepared polymer. Morphology and structure were studied through scanning electron microscopy (SEM), transmission electron spectroscopy (TEM), and dynamic light scattering (DLS). The structure of the hybrid consisted of nanosilica, 10 nm in mean diameter, uniformly dispersed in the pHEMA phase with strong interactions between the phases. Nevertheless, the swelling ratio of the hybrid was comparable to pHEMA. Using FT-IR spectroscopy, SEM and energy dispersive system (EDS), XRD analysis in vitro bioactivity of the hybrid, due to the inorganic phase, was ascertained therefore, the obtained hybrid can be used to make bioactive scaffold for bone engineering. [ABSTRACT FROM AUTHOR]

A novel hydrogel based on 2-hydroxyethyl- methacrilate and SiO2 nanoparticles was prepared. The filler was added at a concentration of 30% w/w of silica nanoparticles to the mass of polymer. The composite material was characterised as far as concerns swelling behaviour in comparison to pHEMA. Swelling ratio of modified pHEMA was higher. Bioactivity of both SiO2 nanoparticles and the modified hydrogel was evaluated by soaking samples into a simulated body fluid (SBF). FT-IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive system (EDS) results suggest silica nanoparticles keep bioactive in the polymer. SiO2 filler in a p(HEMA) matrix makes the composite bioactive. Therefore, these composites can be used to make bioactive scaffold for bone engineering. [ABSTRACT FROM AUTHOR]

Background: Pyro-electrohydrodynamic jetting (p-jet) has emerged recently as a promising technique for biosensing applications, through the concentration of highly diluted biomolecules in fluorescent spots at microscale. However, a great challenge still remains in optimizing the binding strategy for the sensing interface, enabling the detection of low abundance proteins through immunofluorescence protocols. Indeed, the surface of reaction can be functionalized with different chemical groups able to bind the target molecule with a strong interaction, prior to the p-jet spots decreasing the possibility to lose sensitivity after the common rinsing steps., Results: Here, we characterize the immobilization of a model protein, specifically the bovine serum albumin (BSA), in the concentrated p-jet spots to demonstrate the reliability of the technique for highly sensitive immunodetection assays. We first performed spectroscopic measurements on BSA deposited through pipette spots at relatively high concentrations and we achieved a higher efficiency in case of the covalent bond by using the carbonate buffer and the epoxy-based slides. We then tested the covalent setting in case of the p-jet spots with highly diluted samples of pre-labelled BSA. A significant concentration-dependent behavior of the signal was obtained down to picogram levels. Finally, an immunofluorescent protocol was settled with the p-jet spots and a Limit of the Detection (LOD) of 0. 27 pg/mL was reached., Significance: The demonstration here that the p-jet spots are compatible with immunodetection procedures and provide a LOD down to 0.27 pg/mL, launches the p-jet technique towards the development in future of a point-of-care (POC) diagnostic tool. This would become a major force in analytical chemical laboratories. The identification of highly diluted biomarkers from peripheral body fluids would help clinicians performing early diagnosis, overcoming the limitations of the traditional immunochemistry tests, such as the enzyme-linked immunosorbent assay (ELISA)., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this work, we report on the synthesis and properties of a new sensitizer for photodynamic therapy applications, constituted by a ruthenium(ii) complex (1) featuring a ligand inspired from natural isoquinoline alkaloids. The spectroscopic analysis revealed that 1 is characterized by an intense red emission ( λ em = 620 nm, Φ = 0.17) when excited at 550 nm, a low energy radiation warranting for a safe therapeutic approach. The phototoxicity of 1 on human breast cancer (Hs578T) and melanoma (A375) cell lines was assessed after irradiation using a LED lamp (525 nm, total fluence 10 J cm -2 ). In vitro biological assays indicated that the cytotoxicity of 1 was significantly enhanced by light reaching IC 50 values below the micromolar threshold. The cell damage induced by 1 proved to be strictly connected with the overproduction of reactive oxygen species (ROS) responsible for mitochondrial dysfunction leading to the activation of caspases and then to apoptosis, and for DNA photocleavage leading to cell cycle arrest., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Here we demonstrate for the first time that an antibody-gold nanoparticles (AuNPs)-polymer conjugate thin-film biosensor can easily be fabricated to selectively capture Tau protein. Gold nanoparticles (AuNPs) are employed as sensing elements, thus capitalizing on their propensity to undergo assembly or disassembly in response to the adsorption or conjugation of various biomolecules on their surface, thereby forming robust interactions with the target analyte. We show that the Tau protein in its different aggregation phases can be detected, by restricting the reaction area on the solid thin polymer film and thus reducing the diffusion effects usually encountered in immunosensors. A limit of detection (LOD) of 460 pg/mL was reached, demonstrating a great potential for detecting Tau in aggregation states. This sensor based on thin polymer film could open new routes for sensing and monitoring Tau protein in biological assays and biomedical diagnosis., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

TiO 2 nanoparticles loaded with pistachio shell lignin (8 % and 29 % w/w) were prepared by a hydrothermal wet chemistry approach. The efficient interaction at the molecular level of the biomacromolecule and inorganic component was demonstrated by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Visible (UV-Vis), Fourier transform infrared (FT-IR), dynamic light scattering (DLS), and electron paramagnetic resonance (EPR) analysis. The synergistic combination of lignin and TiO 2 nanoparticles played a key role in the functional properties of the hybrid material, which exhibited boosted features compared to the separate organic and inorganic phase. In particular, the hybrid TiO 2 -lignin nanoparticles showed a broader UV-Vis protection range and remarkable antioxidant performance in aqueous media. They could also better protect human skin explants from the DNA damaging effect of UV radiations compared to TiO 2 as indicated by lower levels of p-H2A.X, a marker of DNA damage, at 6 h from exposure. In addition, the samples could protect the skin against the structural damage occurring 24 h post UV radiations by preventing the loss of keratin 10. These results open new perspectives in the exploitation of food-waste derived phenolic polymers for the design of efficient antioxidant materials for skin photoprotection in a circular economy perspective., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Aim: This study examines the prevalence of eating disorders, particularly anorexia and bulimia nervosa, among middle-aged Spaniards, noting their rising incidence in men as well as women. It explores how these disorders relate to sociodemographic factors and lifestyle habits., Methods: A cross-sectional survey was conducted from August 2020 to November 2021 via online platforms. Participants were Spanish nationals aged 31-50 years residing in Spain., Results: Out of 9913 respondents, 96.66% reported no diagnosed eating disorders, while 3.34% reported one or more (0.36% anorexia nervosa; 0.53% bulimia nervosa; 1.97% other eating disorders; 0.48% multiple disorders). Concerns about body image and lack of control over food intake were reported by 50% and 28%, respectively, suggesting potential undiagnosed disorders. Significant BMI differences were noted between healthy individuals and those with anorexia or bulimia., Conclusions: Anorexia and bulimia affect both adolescents and middle-aged individuals, challenging existing stereotypes. The high prevalence of undiagnosed eating disorder behaviors highlights the need for early detection. To address these issues in Spain, targeted awareness programs are essential to reduce stigma and improve service access through clinical, social, and political collaboration.

The development of biosafe theranostic nanoplatforms has attracted great attention due to their multifunctional behavior, reduced potential toxicity, and improved long-term safety. When considering photoacoustic contrast agents and photothermal conversion tools, melanin and constructs like melanin are highly appealing due to their ability to absorb optical energy and convert it into heat. Following a sustainable approach, in this study, silver-melanin like-silica nanoplatforms are synthesized exploiting different bio-available and inexpensive phenolic acids as potential melanogenic precursors and exploring their role in tuning the final systems architecture. The UV-Vis combined with X-Ray Diffraction investigation proves metallic silver formation, while Transmission Electron Microscopy analysis reveals that different morphologies can be obtained by properly selecting the phenolic precursors. By looking at the characterization results, a tentative formation mechanism is proposed to explain how phenolic precursors' redox behavior may affect the nanoplatforms' structure. The antibacterial activity experiments showed that all synthesized systems have a strong inhibitory effect on Escherichia coli, even at low concentrations. Furthermore, very sensitive Photoacoustic Imaging capabilities and significant photothermal behavior under laser irradiation are exhibited. Finally, a marked influence of phenol nature on the final system architecture is revealed resulting in a significant effect on both biological and photoacoustic features of the obtained systems. These melanin-based hybrid systems exhibit excellent potential as triggerable nanoplatforms for various biomedical applications., (© 2024 Wiley‐VCH GmbH.)

It is largely documented that neurodegenerative diseases can be effectively treated only if early diagnosed. In this context, the structural changes of some biomolecules such as Tau, seem to play a key role in neurodegeneration mechanism becoming eligible targets for an early diagnosis. Post-translational modifications are responsible to drive the Tau protein towards a transition phase from a native disorder conformation into a preaggregation state, which then straight recruits the final fibrillization process. Here, we show for the first time the detection of pre-aggregated Tau in artificial urine at femto-molar level, through the concentration effect of the pyro-electrohydrodynamic jet (p-jet) technique. An excellent linear calibration curve is demonstrated at the femto-molar level with a limit of detection (LOD) of 130 fM. Moreover, for the first time we show here the structure stability of the protein after p-jet application through a deep spectroscopic investigation. Thanks to the small volumes required and the relatively compact and cost-effective characteristics, this technique represents an innovative breakthrough in monitoring the early stage associated to neurodegeneration syndromes in different scenarios of point of care (POC) and such as for example in long-term human space exploration missions., Competing Interests: Declaration of competing interest The authors state that they are not aware of any financial or interpersonal conflicts that might have appeared to have an impact on the research presented in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Sustainable active food packaging is essential to reduce the use of plastics, preserve food quality and minimize the environmental impact. Humic substances (HS) are rich in redox-active compounds, such as quinones, phenols, carboxyl, and hydroxyl moieties, making them functional additives for biopolymeric matrices, such as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Herein, composites made by incorporating different amounts of HS into PHBV were developed using the electrospinning technology and converted into homogeneous and continuous films by a thermal post-treatment to obtain a bioactive and biodegradable layer which could be part of a multilayer food packaging solution. The morphology, thermal, optical, mechanical, antioxidant and barrier properties of the resulting PHBV-based films have been evaluated, as well as the antifungal activity against Aspergillus flavus and Candida albicans and the antimicrobial properties against both Gram (+) and Gram (-) bacterial strains. HS show great potential as natural additives for biopolymer matrices, since they confer antioxidant, antimicrobial, and antifungal properties to the resulting materials. In addition, barrier, optical and mechanical properties highlighted that the obtained films are suitable for sustainable active packaging. Therefore, the electrospinning methodology is a promising and sustainable approach to give biowaste a new life through the development of multifunctional materials suitable in the active bio-packaging., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Melanin is a multifunctional biological pigment that recently emerged as endowed with anti-inflammatory, antioxidant, and antimicrobial properties and with high potentialities in skin protection and regenerative medicine. Here, a biomimetic magnesium-doped nano-hydroxyapatite (MgHA) was synthesized and decorated with melanin molecules starting from two different monomeric precursors, i.e. 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and dopamine (DA), demonstrating to be able to polymerize on the surface of MgHA nanostructures, thus leading to a melanin coating. This functionalization was realized by a simple and green preparation method requiring mild conditions in an aqueous medium and room temperature. Complementary spectroscopy and electron imaging analyses were carried out to define the effective formation of a stable coating, the percentage of the organic compounds, and the structural properties of resulting melanin-coated nanostructures, which showed good antioxidant activity. The in vitro interaction with a cell model, i.e. mouse fibroblasts, was investigated. The excellent biocompatibility of all bioinspired nanostructures was confirmed from a suitable cell proliferation. Finally, the enhanced biological performances of the nanostructures coated with melanin from DHICA were confirmed by scratch assays. Jointly our findings indicated that low crystalline MgHA and melanin pigments can be efficiently combined, and the resulting nanostructures are promising candidates as multifunctional platforms for a more efficient approach for skin regeneration and protection., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Giuseppe Vitiello reports financial support was provided by University of Naples Federico II., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Hydrogen is expected to largely contribute to the near-future circular economy. Today, most hydrogen is still produced from fossil fuels or renewable pathways with low efficiency and high cost. Herein, a proof of concept for a novel hydrogen production process is proposed, here named cyan hydrogen , inspired by a combination of the green and blue processes, due to the key role played by water and the low carbon content in the gas phase, respectively. The developed novel process, recently patented and demonstrated at the lab scale, is based on successive steps in which ethanol (5.0 mL) and water (10.0 mL) are alternately fed, with a fixed initial amount of sodium metaborate (2.0 g), in a batch reactor at 300 °C. Preliminary results showed the simultaneous production of a 95% v/v hydrogen stream, a polymeric byproduct with a repetitive carbon pattern -CH 2 -CH 2 -, and a liquid phase rich in oxygenated chemicals at temperatures lower than conventional hydrogen production processes., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Bioinspired nanoparticles have recently been gaining attention as promising multifunctional nanoplatforms for therapeutic applications in cancer, including breast cancer. Here, the efficiency of the chemo-photothermal and photoacoustic properties of hybrid albumin-modified nanoparticles (HSA-NPs) loaded with doxorubicin was evaluated in a three-dimensional breast cancer cell model. The HSA-NPs showed a higher uptake and deeper penetration into breast cancer spheroids than healthy breast cell 3D cultures. Confocal microscopy revealed that, in tumour spheroids incubated with doxorubicin-loaded NPs for 16 h, doxorubicin was mainly localised in the cytoplasm, while a strong signal was detectable at the nuclear level after 24 h, suggesting a time-dependent uptake. To evaluate the cytotoxicity of doxorubicin-loaded NPs, tumour spheroids were treated for up to 96 h with increasing concentrations of NPs, showing marked toxicity only at the highest concentration of doxorubicin. When doxorubicin administration was combined with laser photothermal irradiation, enhanced cytotoxicity was observed at lower concentrations and incubation times. Finally, the photoacoustic properties of doxorubicin-loaded NPs were evaluated in tumour spheroids, showing a detectable signal increasing with NP concentration. Overall, our data show that the combined effect of chemo-photothermal therapy results in a shorter exposure time to doxorubicin and a lower drug dose. Furthermore, owing to the photoacoustic properties of the NPs, this nanoplatform may represent a good candidate for theranostic applications.

Humic acids (HA) consist in a multitude of heterogeneous organic molecules surviving the biological and chemical degradation of both vegetal and animal biomasses. The great abundance and chemical richness of these residues make their valorisation one of the most promising approaches to move towards a circular economy. However, the heterogeneity of the biomass from which HA are extracted, as well as the production process, significantly affects the nature and the relative content of functional groups (i.e. quinones, phenols and carboxylic and hydroxyl moieties), eventually changing HA reactivity and ultimately determining their application field. Indeed, depending on their properties, these substances can be used as flame retardants in the case of pronounced resilience degree (i.e., absent or low reactivity), or as antioxidant or antimicrobial agents in the case of pronounced reactivity, thanks to their redox behaviour. In this work we investigated the flammable, the thermal and the physico-chemical features of HA extracted from different composted biomasses to identify the reactivity or the resiliency of these moieties. Several techniques, including flammability characterization (LIT and MIE), laser diffraction granulometry, TG, XRD analyses, FTIR spectroscopy on both solid and gaseous phases, and Raman spectroscopy were integrated to investigate the correlation among the safety parameters, the distributions of particle sizes, as well as the thermal, the chemical properties of HA powders and the influence of post-extraction processes on HA final properties., Competing Interests: Declaration of competing interest 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., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)