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Most antibacterial applications in nanotechnology are carried out using silver nanoparticles (AgNPs). However, there is a dearth of information on the biological effects of AgNPs on human blood cells. In this study, the cytotoxic and genotoxic potentials of ionic silver (Ag+), AgNP, silver bromide (AgBr), silver chloride (AgCl), and silver iodide (AgI) were evaluated through chromosome aberration (CA) test and cytokinesis-blocked micronucleus (CBMN) test in human cultured lymphocytes in vitro. Furthermore, the potential damages that can cause to DNA were evaluated through alkaline single cell gel electrophoresis (Comet) assay on isolated lymphocytes. The results showed that AgNPs exerted cytotoxic effects by reducing the cytokinesis-block proliferation index and mitotic index at 24 and 48 h. AgNPs also increased micronucleus (MN) formation at both exposure times in the cultured cells. Meanwhile, AgCl had no genotoxic effects on the human lymphocyte cultured cells but had a cytotoxic effect at high doses. AgNP, Ag+, AgBr, and AgI caused substantial DNA damage by forming DNA strand breaks. They may also have clastogenic, genotoxic and cytotoxic effects on human lymphocyte cells. Based on the foregoing findings, silver nanomaterials may have genotoxic and cytotoxic potentials on human peripheral lymphocytes in vitro. [ABSTRACT FROM AUTHOR]

Background: The house fly, Musca domestica, is vector for pathogens and parasites and causes economic damage to livestock by reducing forage conversion efficiency, negatively impacting weight gain and milk production. It has shown resistance to multiple insecticide classes. The aim of this research was to determine the susceptibility levels of seventeen field M. domestica strains to thiamethoxam, a neonicotinoid insecticide, in Türkiye. Methods: Insecticide susceptibility of the house flies to thiamethoxam was determined using the WHO glass jar method. A probit analysis program was used to determine LD50 values, and then the resistance ratios were compared with insecticide-susceptible strain. Results: All strains were ≥18.5-fold resistant to thiamethoxam. The data showed that 10 out of 17 strains had either high or very high resistance levels. Our findings revealed that house flies from solid waste landfills in Samsun, Ankara, and Kocaeli exhibited higher resistance ratios compared to those found in animal shelters. Conversely, in Gaziantep, Antalya, İzmir and Erzurum, the exact opposite trend was observed. Regarding the LD50 values among solid waste storage areas, the lowest rate was obtained from Gaziantep (0.72 gr ai/m²), and the highest rate was obtained from Ankara (9.35 gr ai/m²). Furthermore, regarding the LD50 values among animal shelters, the lowest was obtained from Samsun (0.37 gr ai/m²), and the highest was obtained from Denizli (21800 gr ai/m2). Conclusion: The use of integrated control systems is recommended for controlling house fly populations, including insecticide class rotations for preventing, or at least, delaying the onset of resistance. [ABSTRACT FROM AUTHOR]

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In current study, various types of electrospun scaffolds have been prepared including poly(L-lactide-co-ε-caprolactone), collagen type I, hydroxyapatite nanoparticles (HAp) and silver doped hydroxyapatite particles (Ag-HAp). 13C-NMR, 1H-NMR, FT-IR, XRD, TEM and EDS analyses were performed to characterize the synthesized copolymer and nanoparticles. SEM analysis revealed that the greatest fiber diameter (761 ± 434 nm) was yielded for PLCL fibers, on the other hand, smallest diameter (151 ± 91 nm) was measured for PLCL/COL/Ag-HAp based fibers. According to contact angle test, the existence of collagen and HAp in the blend improved the hydrophilicity of the electrospun scaffolds. The highest tensile strength value (28 MPa) was determined for PLCL/COL based scaffold in the machine direction. Antibacterial efficiency of PLCL/COL/Ag-HAp scaffold was evaluated against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria and remarkable bactericidal effect (99.99%) has been recorded. [ABSTRACT FROM AUTHOR]

Nanocomposites attract the attention of researchers due to the increasing demand on materials having unique properties. Incorporation of nanoparticles into polymers considerably improves some materials properties such as thermal stability. In current study, PMMA/SiO2 hybrid nanocomposites including ungrafted and grafted silica nanoparticles have been prepared. The surfaces of SiO2 nanoparticles were grafted with 3-(methacryloyloxypropyl)trimethoxysilane (MPTS) and 3-(methacryloyloxypropyl)triethoxysilane (MPTES) by sol-gel technique. The structure, morphology and thermal properties of the obtained bulk materials were investigated by FTIR, SEM-EDX, TGA and DSC. Based on the studies of infrared spectroscopy, polymerization of MMA monomers was approved by following the intensity of acrylate group. Thermal characteristics of nanocomposite structures enhanced remarkably as SiO2 nanoparticles were introduced to the polymer matrix and glass transition temperature Tg value reached to the highest (166°C) for MPTES@20% SiO2-PMMA hybrid nanocomposite. According to SEM analysis, the most homogenous structure belonged to MPTES@20% SiO2-PMMA hybrid nanocomposite. [ABSTRACT FROM AUTHOR]

Highlights Poly(lactic acid) (PLA) is a biodegradable and bioactive thermoplastic polymer. It has been widely used for hard tissue applications in orthopedic and dental fields. However, PLA is not able to form a direct bond with bone and this limits its applications. Therefore, PLA and hydroxyapatite (HAp) composites have gained significant attention to improve PLA performance. However, agglomeration of HAp in PLA matrix due to unfavored interfacial interactions between PLA and HAp directly affects the mechanical properties and stability of PLA/HAp composites. In this study, 3‐(glycidyloxypropyl)trimethoxysilane (GLYMO)‐modified HAp particles (G‐HAp) were synthesized and then incorporated into the PLA matrix to prepare PLA/G‐HAp composites. PLA/G‐HAp composites were prepared by mixing G‐HAp at 50 wt% with PLA (10 wt% in chloroform) solution. The resulting mixture was dried, ground, and molded into cylindrical shapes by pressure, and cured under N2 atmosphere. The interface interactions of the obtained composites were elucidated by fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses. It was observed that increased crosslinking density in the interface resulted in rougher surfaces. Thermal analyses demonstrated that Tg of PLA shifted to higher temperatures in parallel with crosslinking density. Additionally, Vicker's hardness tests and compression tests were conducted to determine the effect of interfacial crosslinking, and improved hardness and Young's modulus were observed. In the final part of study, MTT assay was carried out to evaluate cytotoxicity of composites and PLA/G‐HAp displayed higher cytocompatibility compared to conventional PLA/HAp composite. GLYMO modified HAp led to changes in the surface properties of composites. Increased crosslinking caused rougher surfaces for composites. Tg shifted to higher temperatures in parallel with GLYMO mediated crosslinking. Composites containing GLYMO‐modified HAp particles exhibited significant improvement in mechanical properties. [ABSTRACT FROM AUTHOR]

The reflux method was utilized for the synthesis of 5% Sn-doped TiO2 nanopowder. Surfaces of the TiO2 particles were modified with 3-glycidoxypropyltrimethoxysilane (glymo) and glass surfaces were coated with this solution by a spin-coating process. Molar ratios of TiO2 :glymo were 0.25, 0.5, 2.5, and 7.5 in the films. Nanocomposite films were cured at 130 ° C. Adhesions of the obtained films were classified as 5B and pencil hardness increased with the increase in the ratio of the TiO2 in the films. Film thickness decreased from 5 μm to 0.3 μm when TiO2 :glymo was increased from 0.25 to 7.5. The obtained films had sufficient mechanical integrity, and they were photocatalytically active and could degrade rhodamine B. The sample having a TiO2 :glymo ratio of 7.5 presented the highest photoactivity. Lowtemperature curing brings the advantage of utilization of the films on polymer substrates and also there is no need for a barrier layer between the coating and the substrate. [ABSTRACT FROM AUTHOR]

The nanotechnology industry, a rapidly growing industry, can have substantial impacts on economy, society and environment. Silica nanoparticles (SNPs) are used as food additive in many processed foods, in pharmaceutical drug tablets, glass, electronics and as hydrophobic anticancer drug. Studies on the genotoxic risk related with the new emerging nanomaterials are of increasing interest, mainly on those compounds with limited information on their potential genotoxic risk. In this study, we have evaluated the genotoxicity of different concentration of both the microparticulated form (silicon dioxide, SMP) and nanoparticles (15nm) of Silica on Allium cepa root meristem cells. Onion bulbs were exposed to SNP/SMP in solution. Our results show that the DNA damage in the cells exposed to all concentrations of SNP are statistically significant in comparison to the control cells, while the DNA damage in the cells exposed to only the highest concentration (100 pg/mL) of microparticulated silica is statistically significant in comparison to the control cells. We can conclude that the microparticulated silica were not able to increase the DNA damage in low concentrations, but all applied doses of SNP are capable of inducing high levels of DNA damage. [ABSTRACT FROM AUTHOR]

Biomaterials are engineered products that are widely used in many areas of medicine fields such as orthopaedic applications, facial and maxillofacial surgery, artificial heart parts, metal parts, and implantable devices. These materials are widely used in medicine because they are biocompatible with the organism, non-allergic, and are resistant to physical and chemical factors. Hydroxyapatites are bioactive calcium phosphate ceramics that are compatible with tissues. Nano-sized hydroxyapatite has been produced to increase their bioactivity. Although there are advantages to the use of nanoparticles in medicine and therapy, the potential toxicity of these compounds on the ecosystem and human health are of concern. One of the key issues to be investigated is whether the different forms of the same nanoparticle will cause differences in genotoxicity. Herein, the potential genotoxic effects of rod and round forms of nano-sized hydroxyapatites (nHAs) were evaluated using the Allium cepa Single Cell Gel Electrophoresis (SCGE) method. Results had shown that the round form of nHA in the A. cepa meristem root tip cells caused statistically significant genotoxicity at 25 µg/mL concentration in terms of tail intensity and tail moment. This study indicated small-sized-nanohydroxyapatite-induced genotoxicity and cell death in A. cepa. This study has shown that the physical properties of nanoparticles affect potential toxicity mechanisms. [ABSTRACT FROM AUTHOR]