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Catheter-associated urinary tract infections (CAUTI) are among the most common bacterial infections associated with prolonged hospitalization and increased healthcare expenditures. Despite recent advances in the prevention and treatment of these infections, there are still many challenges remaining, among them the creation of a durable catheter coating, which prevents bacterial biofilm formation. The current work reports on a method of protecting medical tubing endowed with antibiofilm properties. Silicone catheters coated sonochemically with ZnO nanoparticles (NPs) demonstrated excellent antibiofilm effects. Toward approval by the European Medicines Agency, it was realized that the ZnO coating would not withstand the regulatory requirements of avoiding dissolution for 14 days in artificial urine examination. Namely, after exposure to urine for 14 days, the coating amount was reduced by 90%. Additional coatings with either carbon or silica maintained antibiofilm activity against Staphylococcus aureus while resisting dissolution in artificial urine for 14 days (C- or SiO 2 -protected catheters exhibited only 29% reduction). HR-SEM images of the protected catheters indicate the presence of the ZnO coating as well as the protective layer. Antibiofilm activity of all catheters was evaluated both before and after exposure to artificial urine. It was shown that before artificial urine exposure, all coated catheters showed high antibiofilm properties compared to the uncoated control. Exposure of ZnO-coated catheters, without the protective layer, to artificial urine had a significant effect exhibited by the decrease in antibiofilm activity by almost 2 orders of magnitude, compared to unexposed catheters. Toxicity studies performed using a reconstructed human epidermis demonstrated the safety of the improved coating. Exposure of the epidermis to ZnO catheter extracts in artificial urine affects tissue viability compared with control samples, which was not observed in the case of ZnO NPs coating with SiO 2 or C. We suggest that silica and carbon coatings confer some protection against zinc ions release, improving ZnO coating safety.

The identification of health risks arising from occupational exposure to submicron/nanoscale materials is of particular interest and toxicological investigations designed to assess their hazardous properties can provide valuable insights. The core-shell polymers poly (methyl methacrylate)@poly (methacrylic acid-co-ethylene glycol dimethacrylate) [PMMA@P (MAA-co-EGDMA)] and poly (n-butyl methacrylate-co-ethylene glycol dimethacrylate)@poly (methyl methacrylate) [P (nBMA-co-EGDMA)@PMMA] could be utilized for the debonding of coatings and for the encapsulation and targeted delivery of various compounds. The hybrid superabsorbent core-shell polymers poly (methacrylic acid-co-ethylene glycol dimethacrylate)@silicon dioxide [P (MAA-co-EGDMA)@SiO 2 ] could be utilized as internal curing agents in cementitious materials. Therefore, the characterization of their toxicological profile is essential to ensure their safety throughout manufacturing and the life cycle of the final products. Based on the above, the purpose of the present study was to assess the acute toxic effects of the above mentioned polymers on cell viability and on cellular redox state in EA. hy926 human endothelial cells and in RAW264.7 mouse macrophages. According to our results, the examined polymers did not cause any acute toxic effects on cell viability after any administration. However, the thorough evaluation of a panel of redox biomarkers revealed that they affected cellular redox state in a cell-specific manner. As regards EA. hy926 cells, the polymers disrupted redox homeostasis and promoted protein carbonylation. Concerning RAW264.7 cells, P (nBMA-co-EGDMA)@PMMA caused disturbances in redox equilibrium and special emphasis was placed on the triphasic dose-response effect detected in lipid peroxidation. Finally, P (MAA-co-EGDMA)@SiO 2 activated cellular adaptive mechanisms in order to prevent from oxidative damage., 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. Published by Elsevier Inc.)

The demand for improved indoor air quality, especially during the pandemic of Covid-19, has led to renewed interest in antiviral and antibacterial air-conditioning systems. Here, air filters of vehicles made of nonwoven polyester filter media were sonochemically coated with CuO nanoparticles by a roll-to-roll coating method. The product, aimed at providing commuters with high air quality, showed good stability and mechanical properties and potent activity against Escherichia coli and Staphylococcus aureus bacteria, H1N1 influenza, and two SARS-CoV-2 variants. The filtering properties of a coated filter were tested, and they were similar to those of the uncoated filter. Leaching tests as a function of airflow were conducted, and the main outcome was that the coating was stable and particles were not detached from the coated media. Extension to other air-conditioning systems was straightforward.

Sonochemistry was applied in the last few years for coating surfaces of various substrates for imparting desired properties to the surface. In the current paper the coating of cucumbers with NaCl nanoparticles and apples with honey nanoparticles was accomplished by applying the sonochemical method. In both coating the nanoparticles were deposited from aqueous solutions. The products were characterized by Inductively coupled plasma, Dynamic light scattering, Scanning electron microscopy, and Nuclear magnetic resonance., (© Association of Food Scientists & Technologists (India) 2021.)

Simultaneous water and ethanol-based synthesis and coating of copper and zinc oxide (CuO/ZnO) nanoparticles (NPs) on bandages was carried out by ultrasound irradiation. High resolution-transmission electron microscopy demonstrated the effects of the solvent on the particle size and shape of metal oxide NPs. An antibacterial activity study of metal-oxide-coated bandages was carried out against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). CuO NP-coated bandages made from both water and ethanol demonstrated complete killing of S. aureus and E. coli bacteria within 30 min., whereas ZnO NP-coated bandages demonstrated five-log reductions in viability for both kinds of bacteria after 60 min of interaction. Further, the antibacterial mechanism of CuO/ZnO NP-coated bandages is proposed here based on electron spin resonance studies. Nanotoxicology investigations were conducted via in vivo examinations of the effect of the metal-oxide bandages on frog embryos (teratogenesis assay- Xenopus ). The results show that water-based coatings resulted in lesser impacts on embryo development than the ethanol-based ones. These bandages should therefore be considered safer than the ethanol-based ones. The comparison between the toxicity of the metal oxide NPs prepared in water and ethanol is of great importance, because water will replace ethanol for bulk scale synthesis of metal oxide NPs in commercial companies to avoid further ignition problems. The novelty and importance of this manuscript is avoiding the ethanol in the typical water:ethanol mixture as the solvent for the preparation of metal oxide NPs. Ethanol is ignitable, and commercial companies are trying the evade its use. This is especially important these days, as the face mask produced by sonochemistry (SONOMASK) is being sold all over the world by SONOVIA, and it is coated with ZnO.

There is a huge demand for materials capable of simple detection or separation after conjugation with specific biologic substances when applied as a diagnostic tools. Taking into account the photoluminescence properties of C-dots and the highly magnetic properties of Fe(0), a new hybrid composite of these components was synthesized via ultrasound irradiation. The material was fully characterized by various physicochemical techniques. The main goal of the current study was to obtain a highly magnetic and intense fluorescent hybrid material. The goal was achieved. In addition, magnetic particles tended to agglomerate. The new hybrid can be suspended in ethanol, which is an additional feature of the current research. The dispersion of the hybrid nanoparticles in ethanol was achieved by utilizing the interaction of iron particles with C-dots which were decorated with functional groups on their surface. The newly formed hybrid material has potential applications in diagnostic by conjugating with specific antibodies or with any other biologic compounds. Such application may be useful in detection of various diseases such as: cancer, tuberculosis, etc.

Two crystalline and five amorphous benzimidazole polymers (BINP) were synthesized and conjugated to porous silica via amine and aldehyde-based materials by a simple reflux procedure. The resulting polymers were subject to thermal analysis for monitoring and quantification of the adsorption and desorption of CO 2 . All the polymers were capable of adsorbing CO 2 from a flowing stream of only 80 mL/min at 25 °C. The adsorbed CO 2 onto the polymers were effectively desorbed at room temperature, illustrating the potential application of such polymers for repeated adsorption/desorption of CO 2 . The CO 2 adsorption capacities of these polymers were dependent upon their nitrogen content, specific surface area, and pore size. The available nitrogen atoms for binding to the carbon of CO 2 via tetrel bonds also plays an important role in the capture of this gas. Minimal and much lower CO 2 adsorption was also noted with two crystalline polymers, compared to the five amorphous counterparts. Intermolecular hydrogen bonding and π-π interaction effectively prevented the polymer N sites of the crystalline polymers from interacting with polarized CO 2 molecules.

Antimicrobial textiles can contribute to the fighting against antibiotic resistance pathogenic microorganisms. Polypyrrole is a conjugated polymer that exerts a biocidal action thanks to positive charges on its backbone chain produced during it synthesis. In this work, dispersions of stable polypyrrole nanoparticles were produced by chemical oxidative polymerization at room temperature in water. An ultrasound-assisted coating process was then used to effectively treat a polyester fabric with the nanoparticles to obtain an optimal antibacterial coating which efficiently eradicates the bacteria. The results showed that the treated fabric with about 4 g/m 2 of polypyrrole had log bacteria reductions of 6.0 against Staphylococcus aureus and 7.5 against Escherichia coli. The combination of a polypyrrole synthesis in the form of water nanoparticles dispersions and a continuous coating of fabrics supported by ultrasound overcomes some issues of upscaling of the traditional in-situ chemical deposition used until now for the production of polypyrrole-coated textiles., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

In this review, we report the functionalization of textiles composed of nanoscale reactive materials in the treatment of wounds and skin diseases such as acne. In view of the growing demand for high-quality textiles, much research is focused on the creation of antimicrobial finishings for fabrics, in order to protect customers from pathogenic or odorgenerating microorganisms. We present coatings from inorganic, organic and biochemical nanoparticles (NPs) on surfaces that impart the ability to kill bacteria, avoid biofilm formation and speed up the recovery of wounds. In all three cases, sonochemistry is used for immobilizing the nanoparticles on the surfaces. The Introduction broadly covers the progress of nanotechnology in the fields of wound and skin care. The first section of this review outlines the mechanism of the ultrasound-assisted deposition of nanoparticles on textiles. The coating can be performed by an in-situ process in which the nanoparticles are formed and subsequently thrown onto the surface of the fabrics at a very high speed. This approach was used in depositing metal-oxide NPs such as ZnO, CuO and Zn-CuO or the organic NPs of tannic acid, chitosan, etc. on textiles. In addition, the sonochemical process can be used as a "throwing stone" technique, namely, previously synthesized or commercially purchased NPs can be placed in the sonication bath and sonicated in the presence of the fabric. The collapse of the acoustic bubble in the solution causes the throwing of the immersed commercial NPs onto the textiles. This section will also outline why sonochemical deposition on textiles is considered the best coating technique. The second section will discuss new applications of the sonochemically- coated textiles in killing bacteria, avoiding biofilm formation and more. Two points should be noted: 1) the review will primarily report results obtained at Bar-Ilan University and 2) since for all textiles tested in our experiments (cotton, polyester, nylon, nonwoven) similar results were obtained, the type of textile used in a specific experiment will not be mentioned - textiles will be discussed in general. It is also worth emphasizing that this review concentrates only on the sonochemical coating of textiles, ignoring other deposition techniques., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

: Cochlear implants (CI) restore functional hearing in the majority of deaf patients. Despite the tremendous success of these devices, some limitations remain. The bottleneck for optimal electrical stimulation with CI is caused by the anatomical gap between the electrode array and the auditory neurons in the inner ear. As a consequence, current devices are limited through 1) low frequency resolution, hence sub-optimal sound quality and 2), large stimulation currents, hence high energy consumption (responsible for significant battery costs and for impeding the development of fully implantable systems). A recently completed, multinational and interdisciplinary project called NANOCI aimed at overcoming current limitations by creating a gapless interface between auditory nerve fibers and the cochlear implant electrode array. This ambitious goal was achieved in vivo by neurotrophin-induced attraction of neurites through an intracochlear gel-nanomatrix onto a modified nanoCI electrode array located in the scala tympani of deafened guinea pigs. Functionally, the gapless interface led to lower stimulation thresholds and a larger dynamic range in vivo, and to reduced stimulation energy requirement (up to fivefold) in an in vitro model using auditory neurons cultured on multi-electrode arrays. In conclusion, the NANOCI project yielded proof of concept that a gapless interface between auditory neurons and cochlear implant electrode arrays is feasible. These findings may be of relevance for the development of future CI systems with better sound quality and performance and lower energy consumption. The present overview/review paper summarizes the NANOCI project history and highlights achievements of the individual work packages.

Chronic wound fluids have elevated concentration of human neutrophil elastase (HNE) which can be used as inflammation/infection marker. Our goal is to develop functional materials for fast diagnosis of wound inflammation/infection by using HNE as a specific marker. For that, fluorogenic peptides with a HNE-specific cleavage sequence were incorporated into traditional textile dressings, to allow real-time detection of the wound status. Two different fluorogenic approaches were studied in terms of intensity of the signal generated upon HNE addition: a fluorophore 7-amino-4-trifluormethylcoumarin (AFC) conjugated to a HNE-specific peptide and two fluorophore/quencher pairs (FAM/Dabcyl and EDANS/Dabcyl) coupled to a similar peptide as a Förster resonance energy transfer (FRET) strategy. Also, two immobilization methods were tested: sonochemistry immobilization onto a cotton bandage and glutaraldehyde (GTA)-assisted chemical crosslinking onto a polyamide dressing. The immobilized fluorogenic AFC peptide showed an intense fluorescence emission in the presence of HNE. HNE also induced an enhanced fluorescent signal with the EDANS/Dabcyl FRET peptide which showed to be a more sensitive and effective strategy than the AFC peptide. However, its chemical immobilization onto the polyamide dressing greatly decreased its detection, mainly due to the more difficult access of the enzyme to the cleavage sequence of the immobilized peptide. After optimization of the in situ immobilization, it will be possible to use these fluorescence-functionalized dressings for an effective and specific monitoring of chronic wounds by simply using a portable ultraviolet (UV) light source. We envision that the development of this point-of-care medical device for wound control will have a great impact on patient's life quality and reduction of costs on health care system.

This report presents a method for producing large quantities of biodiesel from waste cooking oil (WCO). Preliminary studies on optimization of the WCO transesterification process in a continuous-flow microwave reactor are carried out using commercial SrO as a catalyst. The SrO catalyst can be separated and reused for five reaction cycles without loss in activity. Challenges like mass flow and pressure drop constraints need to be surmounted. SrO nanoparticles deposited on millimeter-sized (3-6mm) silica beads (41wt% SrO/SiO 2 ) are prepared and evaluated as a substitute for the SrO catalyst. A WCO conversion value to biodiesel as high as 99.2wt% was achieved with the reactor packed with 15g of 41wt% SrO/SiO 2 catalyst in 8.2min with 820mL of feed. Excellent performance of the fixed-bed catalyst without loss in activity for a lifetime of 24.6min converting a feed of 2.46L to FAME was observed., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A microwave assisted feasible process for the production of bioethanol from Ficus religiosa leaves was developed. Under the process conditions (8 min. microwave irradiation, 1 M HCl), 10.1 wt% glucose yield was obtained from the leaves. Microwave based hydrolysis process yielded higher glucose content (10.1 wt%) compared to the conventional hydrothermal process (4.1 wt%). Upon fermentation of the hydrolysate using Baker's yeast, 3 wt% (dry wt. basis) of bioethanol was produced., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The sonochemical technique has already been proven as one of the best coating methods for stable functionalization of substrates over a wide range of applications. Here, we report for the first time on the simultaneous sonochemical dyeing and coating of textiles with antibacterial metal oxide (MO) nanoparticles. In this one-step process the antibacterial nanoparticles are synthesized in situ and deposited together with dye nanoparticles on the fabric surface. It was shown that the antibacterial behavior of the metal oxides was not influenced by the presence of the dyes. Higher K/S values were achieved by sonochemical deposition of the dyes in comparison to a dip-coating (exhaustion) process. The stability of the antibacterial properties and the dye fastness was studied for 72 h in saline solution aiming at medical applications.

The ability to scale-up the sonochemical coating of medical textiles with antibacterial nanoparticles is demonstrated in the current paper. A roll-to-roll pilot installation to coat textiles was built taking into consideration the requirements of the sonochemical process. A long-run experiment was conducted in which 2500 m of fabric were coated with antibacterial ZnO nanoparticles (NPs). The metal oxide NPs were deposited from an ethanol:water solution. In this continuous process a uniform concentration of coated NPs over the length/width of the fabric was achieved. The antibacterial efficiency of the sonochemically-coated textiles was validated in a hospital environment by a reduction in the occurrence of nosocomial infections. NP-coated bed sheets, patient gowns, pillow cover, and bed covers were used by 21 patients. For comparison 16 patients used regular textiles. The clinical data indicated the reduced occurrence of hospital-acquired infections when using the metal oxide NP-coated textiles. In order to reduce the cost of the coating process and considering safety issues during manufacturing, the solvent (ethanol:water) (9:1 v:v) used for the long-run experiment, was replaced by water. Although lesser amounts of ZnO NPs were deposited on the fabric in the water-based process the antibacterial activity of the textiles was preserved due to the smaller size of the particles., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Much effort has been devoted to the design of effective biomaterials for nerve regeneration. Here, we report the novel use of silver nanoparticles (AgNPs) as regenerative agents to promote neuronal growth. We grew neuroblastoma cells on surfaces coated with AgNPs and studied the effect on the development of the neurites during the initiation and the elongation growth phases. We find that the AgNPs function as favorable anchoring sites, and the growth on the AgNP-coated substrates leads to a significantly enhanced neurite outgrowth. Cells grown on substrates coated with AgNPs have initiated three times more neurites than cells grown on uncoated substrates, and two times more than cells grown on substrates sputtered with a plain homogenous layer of silver. The growth of neurites on AgNPs in the elongation phase was enhanced as well. A comparison with substrates coated with gold nanoparticles (AuNPs) and zinc oxide nanoparticles (ZnONPs) demonstrated a clear silver material-driven promoting effect, in addition to the nanotopography. The growth on substrates coated with AgNPs has led to a significantly higher number of initiating neurites when compared to substrates coated with AuNPs or ZnONPs. All nanoparticle-coated substrates affected and promoted the elongation of neurites, with a significant positive maximal effect for the AgNPs. Our results, combined with the well-known antibacterial effect of AgNPs, suggest the use of AgNPs as an attractive nanomaterial - with dual activity - for neuronal repair studies.

The CuO-ZnO composite was deposited onto two kinds of titania supports, which are synthetic mesoporous TiO2 and commercial TiO2 P25 (Degussa), via the ultrasound assisted precipitation and incipient wetness impregnation (IWI) methods, respectively. The catalysts were tested for WGS reaction in the temperature range of 200-400 °C, and the best catalytic performance was achieved for the sonochemically prepared catalysts supported on the commercial TiO2 P25, which contains well crystallized anatase and rutile phases. Although the synthetic mesoporous TiO2 has a higher surface area, its textural structure is not stable under the reaction conditions, leading to gradual deactivation of the CuO-ZnO/TiO2 catalyst. It is found that the sonochemical preparation offers at least two advantages: (1) generation of mesopores on the catalyst surface and (2) doping of ZnO into the CuO phase. The doping of ZnO, particularly in the case of commercial TiO2 P25, provides high activity and extra stability to the active phase of Cu(0). These new findings provide new insights into the design and development of better heterogeneous catalysts for WGS reaction.

Zinc-doped copper oxide nanoparticles are synthesized and simultaneously deposited on cotton fabric using ultrasound irradiation. The optimization of the processing conditions, the specific reagent ratio, and the precursor concentration results in the formation of uniform nanoparticles with an average size of ≈30 nm. The antibacterial activity of the Zn-doped CuO Cu₀.₈₈Zn₀.₁₂O in a colloidal suspension or deposited on the fabric is tested against Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) bacteria. A substantial enhancement of 10,000 times in the antimicrobial activity of the Zn-CuO nanocomposite compared to the pure CuO and ZnO nanoparticles (NPs) is observed after 10 min exposure to the bacteria. Similar activities are observed against multidrug-resistant bacteria (MDR), (i.e., Methicillin-resistant S. aureus and MDR E. coli) further emphasizing the efficacy of this composite. Finally, the mechanism for this enhanced antibacterial activity is presented., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Silver nanoparticles (NPs) were synthesized sonochemically by the reduction of silver ions with ethylene glycol and simultaneously deposited on different forms of TiO 2 powders (commercial Degussa P-25, synthetic anatase and mesoporous titania). The Ag-TiO 2 nanocomposites were characterized by X-ray electron diffraction (XRD), transmission electron microscopy (TEM), energy-dispersed X-ray analysis (EDX), UV absorption spectroscopy (UV), Z-potential measurements and electron paramagnetic resonance (EPR). The results demonstrated homogeneous distribution of silver nanoparticles ∼3 nm in size, strongly attached to the surface of titania. The antimicrobial properties of Ag-TiO 2 were tested against a number of Gram-positive and Gram-negative bacteria. A high bactericidal effect was found in the absence of UV light. The reduction in bacterial viability was between 3 and 4.2 logs. Based on the experimental data it was concluded that enhanced antimicrobial activity of the Ag-TiO 2 originated from both the oxidative stress generated by silver nanoparticles and the presence of silver ions on the surface of the silver-titania composite.

Nanostructured chitosan (CS) and a chitosan-Zn based (Zn-CS) complex have been synthesized and simultaneously deposited on cotton fabrics using ultrasound. SEM measurements revealed that the coating consists of nanoparticles (NPs) of ca. 40 nm in diameter, homogeneously dispersed along the yarns. XANES studies pointed out that the complex consisted of a less than 2.1 nm ZnO core to which the chitosan was bonded. Additionally, FTIR measurements indicated the in situ formation of a Zn-CS complex which is the only deposited material on the cotton surface. The antibacterial properties of the CS and Zn-CS coated textiles were tested against Gram positive and Gram negative bacteria species. More than two-fold increase of the antibacterial activity of Zn-CS NP coated textiles was detected as compared to the fabrics treated with the sonochemically synthesized CS NPs alone. The sonochemical technique appears to be a suitable method for producing organic NPs of soluble compounds, without loss of their intrinsic properties, i.e. the antimicrobial activity of chitosan. Moreover, hybrid nanoorganometallic particles were simultaneously synthesized and deposited on cotton sonochemically.

Titanium oxide (TiO(2)) nanoparticles (NPs) in their two forms, anatase and rutile, were synthesized and deposited onto the surface of cotton fabrics by using ultrasonic irradiation. The structure and morphology of the nanoparticles were analyzed by using characterization methods such as XRD, TEM, STEM, and EDS. The antimicrobial activities of the TiO(2)-cotton composites were tested against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) strains, as well as against Candida albicans. Significant antimicrobial effect was observed, mainly against Staphylococcus aureus. In addition, the combination of visible light and TiO(2) NPs showed enhanced antimicrobial activity., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This work describes a general method for the preparation of salt nanoparticles (NPs) made from an aqueous solution of ionic compounds (NaCl, CuSO(4) and KI). These nanoparticles were created by the application of ultrasonic waves to the aqueous solutions of these salts. When the sonication was carried out in the presence of a glass microscope slide, a parylene-coated glass slide, or a silicon wafer the ionic NPs were embedded in these substrates by a one-step, ultrasound-assisted procedure. Optimization of the coating process resulted in homogeneous distributions of nanocrystals, 30 nm in size, on the surfaces of the substrates. The morphology and structure of each of the coatings were characterized by physical and chemical methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). After 24 h of leaching into water the nanoparticles of the inorganic salts were still present on the slides, and complete leaching of nanoparticles occurred only after 96 h. A mechanism of the ultrasound-assisted coating is proposed.

The preferential oxidation (PROX) of CO in the presence of H(2) is an important step in the production of pure H(2) for industrial applications. In this report, two sonochemical methods (S1 and S2) were used to prepare highly dispersed Ru catalysts supported on mesoporous TiO(2) (TiO(2)(MSP)) for the PROX reaction, in which a reaction gas mixture containing 1% CO + 1% O(2) + 18% CO(2) + 78% H(2) was used. The supported Ru catalysts performed better than the supported Au and Pt catalysts, and the S1 and S2 methods are superior to the impregnation method. The Ru/TiO(2)(MSP) catalysts were active for the PROX reaction below 200 °C and good for the methanation reactions of CO and CO(2) above 200 °C. The presence of residual chlorine in the catalysts severely suppressed their PROX reaction activity, and a higher dispersion of Ru particles led to better catalytic performances. The addition of Au in the Ru/TiO(2)(MSP) catalyst also caused a poorer catalytic activity for both the PROX and the methanation reactions. TPR results showed that in the active catalysts prepared by the S1 and S2 methods, the well dispersed Ru particles, after calcination in air, had a stronger interaction with the support than those in the catalyst prepared by the impregnation method and in the Au-Ru/TiO(2)(MSP) catalyst. In situ CO absorption experiments performed with the diffusion reflectance Fourier transform infra red (DRIFT) method showed that the bridged adsorbed CO species on isolated Ru(0) sites correlated with the catalytic performances, indicating that these isolated Ru(0) sites are the most active sites of the Ru/TiO(2)(MSP) catalysts in the PROX reaction., (This journal is © the Owner Societies 2011)

Colloidal silver has gained wide acceptance as an antimicrobial agent, and various substrates coated with nanosilver such as fabrics, plastics, and metal have been shown to develop antimicrobial properties. Here, a simple method to develop coating of colloidal silver on paper using ultrasonic radiation is presented, and the coatings are characterized using X-ray diffraction (XRD), high resolution scanning electron microscope (HRSEM), and thermogravimetry (TGA) measurements. Depending on the variables such as precursor concentrations and ultrasonication time, uniform coatings ranging from 90 to 150 nm in thickness have been achieved. Focused ion beam (FIB) cross section imaging measurements revealed that silver nanoparticles penetrated the paper surface to a depth of more than 1 μm, resulting in highly stable coatings. The coated paper demonstrated antibacterial activity against E. coli and S. aureus, suggesting its potential application as a food packing material for longer shelf life.

Background/purpose: Magnetic therapy has been popular for ages, but its therapeutic abilities remain to be demonstrated. We aimed to develop a homogeneous, stable dispersion of magnetic nanoparticles in a skin-care preparation, as a tool to analyze the biological and physiological effects of superficial magnetism in skin., Methods: SrFe(12)O(19) nanoparticles were generated by ultrasound, dispersed in glycerol, stabilized in Dermud cream and permanently magnetized. The magnetic cream was applied on the epidermis of human skin organ cultures. The effects on UV-induced cell toxicity, apoptosis and inflammatory cytokine expression were analyzed. A clinical test was performed to check skin moisturization., Results: Nanomagnets were found to be homogenously and stably dispersed. After magnetization, the preparation generated a magnetic field of 1-2 G. Upon cream application, no cytotoxicity and no impairment of cellular vitality were found after 24 and 48 h, respectively. The anti-apoptotic and anti-inflammatory properties of Dermud were not modified, but its long-term effect on moisturization in vivo was slightly increased., Conclusion: Nanomagnetic Dermud cream can be used as a tool to analyze the biological effects of nanomagnets dispersed on the skin surface at the cellular and molecular levels, thus allowing to explore the possible therapeutic uses of superficial magnetism for skin care.

Ultrasound irradiation was applied as a "throwing stones" technique for coating cotton bandages with MgO and Al(2)O(3) commercially obtained nanoparticles. The homogeneous distribution of the nanoparticles without any aggregation on the fabrics was demonstrated. The antibacterial activities of the MgO/Al(2)O(3)-fabric nanocomposite were tested against Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) cultures. A significant bactericidal effect, even in a concentration <1% (by weight), was detected.

Materials obtained by the synergistic combination of nanotechnology and biomedicine are an important source of drug delivery and other health care related applications. The anchoring of amino acids onto the surface of nano-sized magnetite is one such example. Herein, we report on the binding of a semi-essential amino acid, L-arginine, onto the surface of nano magnetite, creating a stable aqueous suspension by an in situ one-step method using sonochemical synthesis. An ex situ two-step process was also attempted, but was soon discarded owing to the relative short duration of the suspension attributed to increase in particle size and lower extent of binding. The initial concentration of the amino acid was found to play an important role in controlling the particle size and also the binding motif. Lower concentrations of arginine were found to favor the formation of elongated tubular structures, while at higher concentrations, the elongated structures were less prominent and arginine was found to be adsorbed onto the surface of the magnetite. This surface-functionalized nanomagnetite with amino acids could become a promising vehicle for drug delivery., (Copyright (c) 2009 Elsevier B.V. All rights reserved.)

The paper presents a successful sonochemical attempt to synthesize mesoporous chiral titania using a chiral inorganic precursor and dodecylamine, as the surfactant template. The resulting porous structure was characterized by nitrogen sorption experiments, transmission electron microscopy, and small-angle XRD. The enantioselectivity of this mesoporous titania after the extraction of the amine was examined by selective adsorption of enantiomers and racemic aqueous solution of camphor. The selective adsorption was measured by circular dichroism (CD) spectroscopy., (Copyright 2009 Elsevier B.V. All rights reserved.)

Interactions between biomolecules and nanoparticles suggest the use of nanoparticles for various medical interventions. The attachment and entry of herpes simplex virus type 1 (HSV-1) into cells involve interaction between viral envelope glycoproteins and cell surface heparan sulfate (HS). Based on this mechanism, we designed silver nanoparticles that are capped with mercaptoethane sulfonate (Ag-MES). These nanoparticles are predicted to target the virus and to compete for its binding to cellular HS through their sulfonate end groups, leading to the blockage of viral entry into the cell and to the prevention of subsequent infection. Structurally defined Ag-MES nanoparticles that are readily redispersible in water were sonochemically synthesized. No toxic effects of these nanoparticles on host cells were observed. Effective inhibition of HSV-1 infection in cell culture by the capped nanoparticles was demonstrated. However, application of the soluble surfactant MES failed to inhibit viral infection, implying that the antiviral effect of Ag-MES nanoparticles is imparted by their multivalent nature and spatially directed MES on the surface. Our results suggest that capped nanoparticles may serve as useful topical agents for the prevention of infections with pathogens dependent on HS for entry.

Zinc oxide (ZnO) nanoparticles were synthesized and deposited on the surface of cotton fabrics using ultrasound irradiation. Optimization of the process resulted in a homogeneous distribution of ZnO nanocrystals, 30 nm in size, on the fabric surface. The mechanism of the ultrasound-assisted coating was proposed. The antibacterial activities of the ZnO-fabric composite were tested against Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) cultures. A significant bactericidal effect, even in a 0.75% coated fabric (wt %), was demonstrated.

Sonochemical irradiation of iron (II) acetate aqueous solution in presence of silver nanopowder resulted in deposition of magnetite nanoparticles on silver nanocrystals, and imparted them with magnetic properties. The Ag-Fe(3)O(4) nanocomposite is well attracted to a permanent magnet, and demonstrates superparamagnetic behavior typical of nanomaterials in a magnetic field. The characterization of the product by X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HR TEM), energy-dispersive X-ray analysis (EDX), and X-ray photoelectron spectroscopy (XPS) reveal the presence of two phases of the silver and the magnetite, but no chemical interaction between them has been found. The strong anchoring of magnetite to the nanosilver surface was explained as a result of local melting of silver when the magnetite nucleus is thrown at the silver surface by high speed sonochemical microjets.

A glass substrate was coated with silver by ultrasound irradiation. The structure and morphology of the nanoparticles in the deposited film were characterized using methods such as XRD, TEM, HR TEM, HRSEM, AFM, TOF-SIMS and optical spectroscopy. It was demonstrated that nucleation and the ensuing growth of the nanoparticles occurs in solution and is influenced by the concentration of the precursor, temperature and time of sonication. TOF-SIMS measurements revealed that silver nanoparticles passed through the glass interface and diffused within the glass substrate up to ∼60 nm. An analysis of the thermal effects accompanying the sonochemical cavitation of micro-bubbles in the solution near the solid surfaces shows that the collision of nanoparticles can lead to their melting and coalescence. Sonochemical deposition takes place layer by layer, so that the completion of the deposition of each layer of nanoparticles is followed by the sintering of adjacent particles and the formation of a close-packed layer. Using PVP as a stabilizing agent, a monolayer coating of silver nanoparticles on the glass surface was obtained. The coated glass demonstrated antibacterial activity.

Silver nanoparticles were synthesized and deposited on different types of fabrics using ultrasound irradiation. The structure of silver-fabric composites was studied by physico-chemical methods. The mechanism of the strong adhesion of silver nanoparticles to the fibers is discussed. The excellent antibacterial activity of the Ag-fabric composite against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) cultures was demonstrated.

Two model catalysts, Au/TiO2/C (S) (sonochemically derived) and Au/TiO2/C (M) (microwave derived), were produced by employing ultrasound irradiation and microwave irradiation, respectively. The deposition of gold colloids onto the support powders, TiO2/C, was accomplished by using a solvated metal atom impregnation (SMAI) method. The SMAI technique provides highly-dispersed gold particles on the TiO2/C support. The catalytic performance of Au based catalysts 1 wt% Au-TiO2/C (S) and 1 wt%Au-TiO2(M)/C (M) have been tested for the oxidation of CO in the temperature range of 0-300 degrees C and compared to that of 1 wt% Au-TiO2 (Degussa-P25). A boost in the conversion of CO was observed for the sonochemically-derived catalyst, Au/TiO2/C (S), at low temperature. Hence, the reactivity order found for CO oxidation is (Au/TiO2/C (S)>Au/TiO2 (P25)>Au/TiO2/C (M)).

Microwave (MW) irradiation was found to be a new technique for coating silver nanoparticles with an average size of approximately 31 nm onto the surface of poly(methyl methacrylate) PMMA beads (3 mm diameter). The microwave polyol reduction was carried out under an argon atmosphere. Silver nanoparticles were obtained by the MW irradiation of a solution mixture containing silver nitrate (or silver acetate), poly(ethylene glycol), ethanol, water, and 24 wt % aqueous ammonia for 5 min in the presence of PMMA beads, yielding a PMMA-nanosilver composite. By controlling the atmosphere and reaction conditions, we could achieve the deposition of silver nanoparticles onto the surface of poly(methyl methacrylate) and vary the amount of the silver anchored to the surface. The resulting silver-deposited PMMA samples were characterized using X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray analysis, high-resolution scanning electron microscopy, X-ray photoelectron spectroscopy, and volumetric titration with potassium thiocyanate (KSCN) according to the Folgard method.

Highly dispersed Pt nanoparticles were incorporated in CeO2 nanopowders by an ultrasound-assisted reduction procedure. The activity of the Pt/CeO2 catalysts was studied in the reaction of the ethyl acetate combustion, and complete conversion was achieved at low temperature. It was demonstrated that the higher dispersion of the CeO2 support, the better the performance of the Pt/CeO2 catalysts. The catalysts were characterized by XRD, TEM, HRTEM, EDX, BET, and XPS. The homogeneous incorporation of 2-4 nm Pt nanoparticles into the interparticle distance of the CeO2 nanopowders was demonstrated. The advantage of the sonochemical method for catalyst preparation, in comparison with the traditional incipient wetness impregnation, was explained as the result of the homogeneity and better dispersion of the active metal phase obtained by ultrasound irradiation.

Porous nickel and cobalt oxides were prepared using their alkoxides as inorganic precursors. The stabilization of the mesostructure is especially critical for divalent elements such as Ni and Co, which do not form any network structure, like silicates. The lack of a network-forming multivalent bond is the probable reason why no stable mesoporous oxides have been synthesized for divalent elements yet. Here we have reported our attempt to synthesize porous oxides of Ni and Co. Octadecylamine has been used as the organic structure-directing agent. The product obtained was put under solvent extraction and calcination at various temperatures to remove the surfactant, followed by characterization using XRD, TEM and BET measurements. The FT/IR and thermal analyses (TGA and DSC) were also carried out for supporting information, such as extent of removal of surfactant from the pores of the metal oxide. A relatively better surface area has been obtained for the Co oxide, but in Ni the surface area found is not as good. A possible reason for that has been discussed. The porous (solvent extracted) cobalt oxide has been used as a catalyst in the oxidation reaction of cyclohexane in mild conditions. The catalyst has shown relatively better conversion of cyclohexane into cyclohexanone and cyclohexanol than the nanostructured cobalt oxide catalyst of regular structure.

Ultrasound radiation can be used to synthesize a variety of mesporous materials. The reaction time is considerably shorter than the conventional methods. Ultrasonic waves can be further used for the insertion of amorphous nanosized catalysts into the mesopores. A detailed study demonstrates that the nanoparticles are deposited as a monolayer on the inner mesopores walls without blocking them. When the ultrasonically prepared catalyst/mesoporous-subtrate composite is used in catalysis a high conversion into product is obtained.