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Mateusz Wierzbicki,1 Magdalena Kot,2 Agata Lange,1 Aleksandra Kalińska,2 Marcin Gołębiewski,2 Sławomir Jaworski1 1Department of Nanobiotechnology, Warsaw University of Life Sciences, Warsaw, 02-786, Poland; 2Animal Breeding Department, Warsaw University of Life Sciences, Warsaw, 02-786, PolandCorrespondence: Sławomir Jaworski, Department of Nanobiotechnology, Warsaw University of Life Sciences, Ciszewskiego 8 street, Warsaw, 02-786, Poland, Email slawomir_jaworski@sggw.edu.plPurpose: Mastitis in dairy cows is a worldwide problem faced by dairy producers. Treatment mainly involves antibiotic therapy, however, due to widespread antibiotic resistance among bacteria, such treatments are no longer effective. For this reason, scientists are searching for new solutions to combat mastitis, which is caused by bacteria, fungi, and algae. One of the most promising solutions, nanotechnology, is attracting research due to its biocidal properties. The purpose of this research was to determine the biocidal properties of nanocomposites as a potential alternative to antibiotics in the control of mastitis, as well as to determine whether the use of nanoparticles and what concentration is safe for the breeder and the animal.Patients and Methods: In this study, the effects of Ag, Au, Cu, Fe, and Pt nanoparticles and their complexes were evaluated in relation to the survival of bacteria and fungi isolated from cattle diagnosed with mastitis, their physicochemical properties, and their toxicity to bovine and human mammary epithelial cells BME-UV1 and HMEC (human microvascular endothelial cells). Moreover, E. coli, S. aureus, C. albicans, and Prototheca sp. invasion was assessed using the alginate bead (bioprinted) model. The NPs were tested at concentrations of 25, 12.5, 6.25, 3.125, 1.56 mg/l for Au, Ag, Cu and Fe NPs, and 10, 5, 2.5, 1.25, 0.625 mg/l for Pt.Results: With the exception of Fe and Pt, all exhibited biocidal properties against isolates, while the AgCu complex had the best effect. In addition, nanoparticles showed synergistic effects, while the low concentrations had no toxic effect on BME-UV1 and HMEC cells.Conclusion: Synergistic effects of nanoparticles and no toxicity to bovine and human cells might, in the future, be an effective alternative in the fight against microorganisms responsible for mastitis, and the implementation of research results in practice would reduce the percentage of dairy cows suffering from mastitis. The problem of increasing antibiotic resistance is posing a global threat to human’s and animal’s health, and requires comprehensive research to evaluate the potential use of nanoparticles – especially their complexes – as well as to determine whether nanoparticles are safe for the breeders and the animals. The conducted series of studies allows further consideration of the use of the obtained results in practice, creating a potentially new alternative to antibiotics in the treatment and prevention of mastitis in dairy cattle.Keywords: cattle, mastitis, bacteria, fungi, nanocomposites

Synthesis of novel cement mortar/polymer nanocomposites for antifungal and antibacterial applications is investigated. The blend solution of polyvinyl pyrrolidone (PVP) and carboxymethyl cellulose (CMC) with various ratios of yttrium oxide (Y2O3 ) nanoparticles is prepared with content of 1 wt.% by weight of cement. The (PVP–CMC–Y2O3 ) nanocomposites are used with cement to fabricate the mortar/(PVP–CMC–Y2O3 ) nanocomposites for biomedical applications. The cement mortar/(PVP–CMC–Y2O3 ) is tested against Aspergillus, Lactose organisms and Proteus organisms. Results show that the inhibition zones increase as Y2O3 nanoparticles’ ratios increase. [ABSTRACT FROM AUTHOR]

The magnetization process in the nanocomposite BiFeO3–Bi2Fe4O9 obtained by the glycine–nitrate combustion, was studied. The magnetic characteristics of the individual compounds BiFeO3 and Bi2Fe4O9 and of the composite were found to be substantially different. The new properties of the synthesized substance are ascribed to the exchange interaction on the interface between the phases. [ABSTRACT FROM AUTHOR]

Aim: To determine the influence of nanocomposites such as nanofilled, nanoceramic and fibre reinforced composite restorative systems on the fracture resistance of maxillary premolars with Class II mesio- occlusodistal (MOD) cavities. Materials and Method: Eighty sound maxillary human premolars were divided into four groups of 20 teeth each. Teeth in the first group were left intact (unprepared) and tested as positive controls. Teeth in the remaining three groups were prepared with MOD cavities and were restored with a nanofilled composite (Ice), a nanoceramic composite (CeramX mono) and a fibre reinforced composite (Tetric N Flow & CeramX mono). All groups were stored in water at 37΀C for 24 hours and thermocycled and then tested in universal testing machine. Statistical analysis was done by Kruskal-Wallis and Mann-Whitney U tests. The level of significance was set at 0.05. Results: Results between each group were statistically significant (P> 0.05) except between nanoceramic and fibre reinforced composite system. Conclusion: Under compressive load testing, all restored teeth had lower cuspal fracture resistance than unprepared control teeth. Nanoceramic showed the highest mean cuspal fracture resistance while nanofilled showed the least and fibre reinforced composite proved to be a true tooth reinforcing agent.

Herein, we successfully prepared sustainable nanocomposites from agriculture waste (rice husk)-derived biochar precursor, and followed by nickel-doped, base-treated titanium dioxide nanomaterials loading for efficient lead (Pb2+) removal from aqueous media. By varying the loading contents of active materials, the optimized sample (Ni 0.01 @Na–TiO 2 /BC) possessed an efficient Pb2+ adsorption capability of 122.3 mg g−1 under the under optimum adsorption parameters, which is attributable to its specific surface area (138.09 m2 g−1) and excess functional sites. Kinetic and Isothermal examination illustrated that Pb2+ adsorption phenomena was well followed through pseudo 2nd order and Langmuir models. In addition, superior Pb2+ ions adsorption selectivity was recorded by optimized sample in a multi-metallic system over other existing ion (such as Cd2+, Mg2+, Ca2+, Cu2+, and Zn2+). Desorption experiments has been performed by using desorbing agent that demonstrates the good regeneration ability of sample. Hence, these findings provide new insight for the biowaste management by converting them into innovative adsorbents for commercial scale environmental remediation. [Display omitted] • Sustainable Ni x @Na–TiO 2 /BC samples prepared for highly selective Pb2+ removal. • Ni@TiO 2 loading impact towards improved properties and performance was evaluated. • Maximum recorded Pb2+ adsorption capacity under optimum condition was 122.3 mg g−1. • Ni x @Na–TiO 2 /BC exhibited efficient Pb2+ adsorption selectivity and recyclability. [ABSTRACT FROM AUTHOR]

Carbon-based nanomaterials have captured significant interest in academics for decades. Recently, graphene has been found to be a promising nanomaterial. In this study, novel functionalized graphene oxide nanoflakes (FGONs) were successfully synthesized using silane coupling agents via a chemical approach and used as a reinforcement in cyanate ester (CE)/bismaleimide (BMI) copolymers. The curing mechanism and thermal properties of the FGONs/CE/BMI nanocomposites were investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetry. The results show that the addition of FGONs not only catalyzed the entire curing process but also increased the thermal stability of the nanocomposites. The flexural and impact strengths reached optimum values of 110 MPa and 10.98 kJ m−2 with a load of 1.0 wt% FGONs, respectively. Moreover, the glass transition temperature and dielectric properties of the nanocomposites were lower than those of the CE/BMI copolymer. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The optimum combination of experimental variable, temperature, time of heat treatment under nitrogen atmosphere and amount of Ni-salt was delineated to find out the maximum yield of nanophase Ni in the silica gel matrix. The size of Ni in the silica gel was found to be 34 and 45 nm for the two chosen compositions, respectively. A statistically adequate regression equation, within 95% confidence limit was developed by carrying out a set of active experiments within the framework of design of experiment. The regression equation is found to indicate the beneficial role of temperature and time of heat treatment. [ABSTRACT FROM AUTHOR]

A novel nanocomposites of modified clay in a glassy epoxy were prepared using a direct melt intercalation technique. The contents of oganoclay were varied with 0, 1, 2, and 3 wt% and N-benzylpyrazinium hexafluoroantimonate (BPH) was used for curing of epoxy matrix as a cationic latent catalyst. Dynamic mechanical analysis (DMA) measurement was performed to examine the glass transition temperature of the nanocomposites. As a result, X-ray diffraction indicated the intercalation of the epoxy chains happening inside the gallery of clay. The nanocomposites showed a higher glass transition temperature and storage modulus than those of the pristine epoxy. The mechanical interfacial properties of the nanocomposites were also investigated and the improvement in tearing energy of 160% over pristine epoxy was obtained. [ABSTRACT FROM AUTHOR]

Investigations to elucidate the structures of the cobalt(III) and manganese(III) complexes of tetra(p-sulfonatophenyl)porphinate anions (M(III)TSPP; M = Co and Mn), intercalated in Mg-Fe/Cl and Mg-Al/Cl layered double hydroxides (LDHs) have been carried out. Powder X-ray diffraction analysis, IR and UV-vis diffuse reflectance spectroscopy of Co(III)TSPP and Mn(III)TSPP intercalated into the interlayer spaces of LDH resulted in their perpendicular alignment against the host layers in the plane of the hybrid. [ABSTRACT FROM AUTHOR]

The present review aims to summarize the research efforts undertaken in the last few years in the development and testing of hydrogel-clay nanocomposites proposed as carriers for controlled release of diverse drugs. Their advantages, disadvantages and different compositions of polymers/biopolymers with diverse types of clays, as well as their interactions are discussed. Illustrative examples of studies regarding hydrogel-clay nanocomposites are detailed in order to underline the progressive researches on hydrogel-clay-drug pharmaceutical formulations able to respond to a series of demands for the most diverse applications. Brief descriptions of the different techniques used for the characterization of the obtained complex hybrid materials such as: swelling, TGA, DSC, FTIR, XRD, mechanical, SEM, TEM and biology tests, are also included. Enlightened by the presented data, we can suppose that hydrogel-clay nanocomposites will still be a challenging subject of global assiduous researches. We can dare to dream to an efficient drug delivery platform for the treatment of multiple affection concomitantly, these being undoubtedly like "a tree of life" bearing different kinds of fruits and leaves proper for human healing., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Phase transitions and nanometre-scale ordered structures of a binary system of a liquid-crystalline amphiphilic diblock copolymer, poly(ethylene oxide)- b-poly{11-[4-(4-butylphenylazo)phenoxy]undecyl methacrylate} [PEO m- b-PMA(Az) n, where m and n are the degrees of polymerization of the PEO and PMA(Az) domains, respectively], and lithium trifluoromethanesulfonate (LiCF3SO3) were investigated by differential scanning calorimetry and small-angle X-ray scattering (SAXS). PEO114- b-PMA(Az)51 formed a highly ordered hexagonally packed PEO cylinder structure in the temperature range below 393 K and transformed to a body-centred-cubic structure in the isotropic state above 393 K. The PEO114- b-PMA(Az)51/LiCF3SO3 systems with various LiCF3SO3 concentrations (molar ratio 0 < LiCF3SO3/EO = fLi < 1) formed the hexagonally packed cylinder structure at room temperature. From the effects of LiCF3SO3 concentration on the phase transitions, the size and the order of the hexagonally packed cylinder structure, it was found that PEO114- b-PMA(Az)51 and LiCF3SO3 formed a complex efficiently at a molar equivalent of three ethylene oxide repeating units per LiCF3SO3 unit. The ordering of the hexagonally packed cylinder structure decreased with increasing LiCF3SO3 concentration and the radius of the PEO cylinder evaluated by SAXS profile fitting increased from 2.7 to 8.3 nm. For the PEO114- b-PMA(Az)51/LiCF3SO3 system with fLi = 1, the hexagonally packed cylinder structure remained even in the isotropic state because the PEO volume fraction (φPEO) increased from φPEO = 0.06 ( fLi = 0) to φPEO = 0.23 ( fLi = 1) on the formation of the LiCF3SO3/PEO complex. [ABSTRACT FROM AUTHOR]