A light-assisted in situ embedment of silver nanoparticles to prepare functionalized fabrics

The potential of dietary nanoparticles to enhance allergenicity of milk proteins: an in vitro investigation

In recent years, the popularity of dietary nanoparticles (NPs) in the food industry as additives has raised concerns because of the lack of knowledge about potential adverse health outcomes ensuing from the interactions of NPs with components of the food matrix and gastrointestinal system. In this study, we used a transwell culture system that consisted of human colorectal adenocarcinoma (Caco-2) cells in the apical insert and Laboratory of Allergic Diseases 2 mast cells in the basal compartment to study the effect of NPs on milk allergen delivery across the epithelial layer, mast cell responses and signaling between epithelial and mast cells in allergenic inflammation. A library of dietary particles (silicon dioxide NPs, titanium dioxide NPs and silver NPs) that varied in particle size, surface chemistry and crystal structures with or without pre-exposure to milk was used in this investigation. Milk-interacted particles were found to acquire surface corona and increased the bioavailability of milk allergens (casein and β-lactoglobulin) across the intestinal epithelial layer. The signaling between epithelial cells and mast cells resulted in significant changes in the early phase and late-phase activation of the mast cells. This study suggested that antigen challenge in mast cells with the presence of dietary NPs may cause the transition of allergic responses from an immunoglobulin E (IgE)-dependent mechanism to a mixed mechanism (both IgE-dependent and IgE-independent mechanisms).

Evaluation of Betacoronavirus OC43 and SARS-CoV-2 Elimination by Zefero Air Sanitizer Device in a Novel Laboratory Recirculation System

Indoor air sanitizers contrast airborne diseases and particularly severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)/Coronavirus disease 2019 (COVID-19). The commercial air sanitizer Zefero (Cf7 S.r.l., San Giovanni La Punta, Italy) works alternatively using a set of integrated disinfecting technologies (namely Photocatalysis/UV mode) or by generating ozone (Ozone mode). Here we evaluated the virucidal efficacy of Zefero setup modes against human Betacoronavirus OC43 and SARS-CoV-2. For this purpose, we designed a laboratory test system in which each virus, as aerosol, was treated with Photocatalysis/UV or Ozone mode and returned into a recirculation plexiglass chamber. Aerosol samples were collected after different times of exposure, corresponding to different volumes of air treated. The viral RNA concentration was determined by qRT-PCR. In Photocatalysis/UV mode, viral RNA of OC43 or SARS-CoV-2 was not detected after 120 or 90 min treatment, respectively, whereas in Ozone mode, viruses were eliminated after 30 or 45 min, respectively. Our results indicated that the integrated technologies used in the air sanitizer Zefero are effective in eliminating both viruses. As a reliable experimental system, the recirculation chamber developed in this study represents a suitable apparatus for effectively comparing the disinfection capacity of different air sanitizers.

Dietary nanoparticles compromise epithelial integrity and enhance translocation and antigenicity of milk proteins: An in vitro investigation

Nanoparticles (NPs) are increasingly being used in the food sector, yet little is known about the potential health risks associated with oral exposure to dietary NPs. In this study, the most widely used NPs in food industry including food grade silicon dioxide (SiO₂), titanium dioxide (TiO₂) and silver (Ag), along with their non-food grade and bulk counterparts, are characterized for physicochemical properties and molecular, cellular, and intracellular effects on human intestinal epithelial cells (Caco-2 and HIEC-6). Silver NPs are the most cytotoxic and induce significant cellular changes in oxidative stress, Ca²⁺ flux and mitochondria function, leading to cellular junction disruption at the lowest exposure concentration. At higher testing concentrations, NPs but not microparticles of SiO₂ and TiO₂ cause sublethal cellular responses and remodel tight junctions without impairing epithelial integrity. To relate the cellular results to key events in GI disorder progression, NPs are exposed to an in vitro co-culture model for cow's milk allergy comprised of Caco-2 and allergy sera-primed mast cells (LUVA). All particle treatments increase the allergen delivery across intestinal epithelium and subsequent allergy responses. Overall, the study has identified a particle-dependent alteration in intestinal epithelium and highlighted potential safety concerns of dietary NPs.

Ag2[Fe(CN)5NO]-Fabricated Hydrophobic Cotton as a Potential Wound Healing Dressing: An In Vivo Approach

There have been reports of different types of wound dressings for various functions and purposes. Cotton being one of the most widely used wound dressing material due to its non-toxic, biodegradable, and other properties is used for fabrication as well as in the form of scaffolds for faster and effective wound closure. Our research team has already demonstrated the role of silver nitroprusside nanoparticles (SNPNPs) for wound healing and antibacterial activity. In the current study, we have developed cotton fabric impregnated with SNPNPs (SNPCFs) which remain photo inert and displayed long-term antimicrobial activity due to the surface modification with the silver nitroprusside complex. These SNPCFs were characterized by various analytical techniques (XRD, FTIR, UV spectroscopy, TGA, TEM, FESEM, EDAX, ICP-OES). The fabricated cotton dressings with nanoparticles showed an improved water contact angle (113-130°) than that of bare cotton gauze (60°) and exhibited more antibacterial property in case of both Gram-negative bacteria (Klebsiella aerogenes and Escherichia coli) and Gram-positive bacteria (Pseudomonas aeruginosa and Bacillus subtilis) even after several washings. The biocompatible nature of SNPCFs was assessed by in vivo chorioallantoic membrane assay that showed no obstruction in the formation of blood vessels. The SNPCFs exhibited better wound healing activity compared to the bare cotton and AgCFs as observed in the C57BL6/J mouse. The histopathological investigation reveals increase in re-epithelialization and deposition of connective tissue. The macrophage (M2) counts in SNPCF-treated skin tissues were supportive of more wound healing activity than mice treated with cotton fabric impregnated with chemically synthesized silver nanoparticles. Based on biodistribution analysis using ICP-OES, the data illustrated that a significant amount of silver is absorbed in the skin tissues of mice as compared to the blood and kidney. Furthermore, the absence of silver from the vital organs (heart, liver, and kidney) corroborates our hypothesis that the SNPCFs can act excellently in treating wounds when topically applied over skin. Thereafter, all these results highlight a strong possibility that SNPCFs exemplify the potential as a new antimicrobial and wound healing agent in future times.

Sustainable Use of Nanomaterials in Textiles and Their Environmental Impact

At present, nanotechnology is a priority in research in several nations due to its massive capability and financial impact. However, due to the uncertainties and abnormalities in shape, size, and chemical compositions, the existence of certain nanomaterials may lead to dangerous effects on the human health and environment. The present review includes the different advanced applications of nanomaterials in textiles industries, as well as their associated environmental and health risks. The four main textile industry fields using nanomaterials, nanofinishing, nanocoatings, nanofibers, and nanocomposites, are analyzed. Different functional textiles with nanomaterials are also briefly reviewed. Most textile materials are in direct and prolonged contact with our skin. Hence, the influence of carcinogenic and toxic substances that are available in textiles must be comprehensively examined. Proper recognition of the conceivable benefits and accidental hazards of nanomaterials to our surroundings is significant for pursuing its development in the forthcoming years. The conclusions of the current paper are anticipated to increase awareness on the possible influence of nanomaterial-containing textile wastes and the significance of better regulations in regards to the ultimate disposal of these wastes.

Silver Nanoparticles as Colorimetric Sensors for Water Pollutants

This review provides an up-to-date overview on silver nanoparticles-based materials suitable as optical sensors for water pollutants. The topic is really hot considering the implications for human health and environment due to water pollutants. In fact, the pollutants present in the water disturb the spontaneity of life-related mechanisms, such as the synthesis of cellular constituents and the transport of nutrients into cells, and this causes long / short-term diseases. For this reason, research continuously tends to develop always innovative, selective and efficient processes / technologies to remove pollutants from water. In this paper we will report on the silver nanoparticles synthesis, paying attention to the stabilizers and mostly used ligands, to the characterizations, to the properties and applications as colorimetric sensors for water pollutants. As water pollutants our attention will be focused on several heavy metals ions, such as Hg(II), Ni(II),Cu(II), Fe(III), Mn(II), Cr(III/V) Co(II) Cd(II), Pb(II), due to their dangerous effects on human health. In addition, several systems based on silver nanoparticles employed as pesticides colorimetric sensors in water will be also discussed. All of this with the aim to provide to readers a guide about recent advanced silver nanomaterials, used as colorimetric sensors in water.

Photo-mediated Biosynthesis of Silver Nanoparticles Using the Non-edible Accrescent Fruiting Calyx of Physalis peruviana L. Fruits and Investigation of its Radical Scavenging Potential and Cytotoxicity Activities

Silver nanoparticles (AgNPs) have been synthesized by various ways but the green technology methods using food waste materials has been accepted now a days for their cost effectiveness, environmental friendly and effective biomedical application. In the present study an attempt has been made to synthesize AgNPs by using the outer accrescent fruiting calyx of Physalis peruviana fruits, a food waste material under different light source condition, and to investigate their cytotoxic activity against the HepG₂ cells as well as their antibacterial and radical scavenging potential. The surface morphology and elemental composition of the biosynthesized AgNPs were evaluated by scanning electron microscopy, energy-dispersive X-ray analysis, and X-ray powder diffraction analysis. Fourier transform infrared spectroscopy of the sample extract and AgNPs was performed to determine the involvement of functional groups in the synthesis, capping, and stabilization process. The AgNPs showed promising cytotoxic activity against the HepG2 cells in a dose-dependent manner. The biosynthesized AgNPs also exhibited moderate antibacterial activity (8.14-10.22 mm inhibition zones) against two Gram-negative pathogenic bacteria with promising radical scavenging potential. Overall, the results highlight the effectiveness of the AgNPs for use in antibacterial wound dressing materials and other biomedical applications for the treatment of critical diseases such as cancer.