Polytetrafluoroethylene (PTFE) has been widely used in bone tissue regeneration and engineering as guided bone regeneration membranes or maxillofacial tissue filling materials. The main reasons for PTFE utilization are its non-toxicity, high chemical resistance, low surface energy and excellent thermal stability. To improve adhesion and proliferation of osteoblasts on originally bio-inert PTFE, plasma activation with subsequent nanodiamond treatment was performed. Nanodiamonds are well-known for their great biocompatibility and non-cytotoxicity with their nanostructure better imitating the nanoscale architecture of natural tissue components. Various studies reported enhanced adhesion, proliferation and osteogenic differentiation of the cells cultivated on nanocrystalline diamond films [1].
Hydrogenated (as-received form) or oxidized detonation nanodiamond particles (size 4-5nm) were deposited on pristine or plasma-activated (8W, 240s) PTFE foils by immersion and ultrasonication (5 min) in colloidal aqueous nanodiamond dispersions (1 mg/mL). Surface morphology and wettability of all prepared PTFE foils were characterized by scanning electron microscopy (SEM) and water contact angle measurements. SEM revealed a nanostructured surface of the foil and nanodiamonds attached to plasma-treated PTFE but not to pristine PTFE. The contact angle was only slightly affected and remained in a hydrophobic range above 100°.
The biocompatibility of PTFE-nanodiamond foils was evaluated by proliferation, metabolic activity and viability rate of primary human osteoblasts hFOB1.19. The plasma activation of PTFE foil significantly improved proliferation, metabolic activity and also viability of human osteoblasts. Contrary to our previous study performed on Saos-2 cells [2], hydrogenated nanodiamond films showed higher metabolic activity and viability of hFOB 1.16 cells than oxidized nanodiamonds.
ACKNOWLEDGEMENTS: This study was supported by the Czech Health Research Council, Ministry of Health of the Czech Republic (grant No. 15-32497A).
REFERENCE: [1] Kopecek, M., et al., Improved adhesion, growth and maturation of human bone-derived cells on nanocrystalline diamond films. Physica Status Solidi a-Applications and Materials Science, 2008. 205(9): p. 2146-2153.; [2] Liskova, J., et al., Osteogenic cell differentiation on H-terminated and O-terminated nanocrystalline diamond films. International Journal of Nanomedicine, 2015. 10: p. 869-884.
Nanoscience has produced many new materials. Erbium (Er), dysprosium (Dy) and zinc (Zn) metals have various applications in new nanotechnology. At the end of the life cycle nanomaterials can be released into the environment. Basidiomycetous fungi produce nonspecific extracellular oxidative enzymes, laccases and peroxidases, which degrade xenobiotics and lignin. Nano-metals can have deleterious impacts to ability of fungi to degrade xenobiotics.
The aim was to test impacts of nano-Er, nano-Dy, nano-Zn, Er, Dy, Zn, Er and their salt forms to degradation of azo violet textile dye by six basidiomycetous fungi. Fungal species were Phlebia radiata (FBCC 43), Pleurotus ostreatus (FBCC 517), Stropharia rugosoannulata (FBCC 474), Trametes pubescens (FBCC 735), Agrocybe praecox (FBCC 477) and Cerrena unicolor (FBCC 387). They were cultivated in miniaturized test systems (1 ml) with nano-Er, nano-Dr and nano-Zn or as their traditional or salt form (0-1000 mg/ l). Biodegradation was measured as decolorization of Remazol Brilliant Violet 5R dye. Scanning electronic microscopic (SEM) pictures showed impacts of metals to the fungus. A. praecox and S. rugosoannulata were more sensitive to nano-Zn and nano-Er than to their traditional form. whereas other four species were similarly sensitive to both forms. All six fungi were similarly sensitive to nano-Dr and those with traditional form. Sensitivity between fungal species varied (EC50 = 10–564 mg Dy/ l, EC50 = 38–790 mg Er/ l, EC50 = 9–637 mg Zn/ l). Sensitivity of fungi to nano- and bulk forms was similar in most cases.
ACKNOWLEDGEMENTS: Funded by Nessling Foundation.
Functionality of body fluids largely depends on their rheological properties. On the other hand, the increased of exposure of the organism to environmental nanoparticles, i.e. desert dust or nanoparticles of carbon black resulting from fuel combustion in a diesel engine was observed. The research focused on investigating the impact of selected nanoparticles (Arizona Dust Nominal 0-3 micron (Powder Technology INC, USA), DEP (Diesel Exhaust Particles)) from the combustion of various diesel fuels on the rheological properties of artificial mucus.
In research artificial mucus (2% and 20% concentration of mucin) [Sosnowski et al., 2009] and nanoparticles’ suspensions in artificial mucus (0.06 and 6 mg/ml) were prepared and their rheological properties (flow curve, viscosity dependence of shear stress, storage modulus and loss modulus) were studied. All rheological parameters were measured by an oscillating rheometer (MCR102, Anton Paar, Austria) at temperatures of 22°C, 36.6°C and 40°C. The size of nanoparticles in water was determined by Malvern Zetasizer. Size distribution by number of nanoparticles are 654.3 nm (100%) for fuel 1, 565.9 nm (100%) for fuel 2, 131.1 nm and 363.7 nm (13.7%, 86.3% respectively) for Arizona Dust. The influence of nanoparticles on mucus rheological properties was observed. The high concentration of nanoparticles increases apparent viscosity while the impact of low concentration of nanoparticles on mucus rheology is negligible. On the other hand the presence of nanoparticles in mucus does not change mucus viscoelastic properties. The viscous properties dominate over elastic properties, both in clean mucus and in mucus with selected nanoparticles.
Cells labeled with iron oxide nanoparticles (ION) can be tracked by magnetic resonance imaging (MRI) in various applications. However, various studies demonstrated toxicity and oxidative stress induction associated with nanoparticles exposure. We analysed biologic effects after exposure of two types of iron oxide nanoparticles (with and without an antioxidative agent; an ascorbic acid) on human neural stem cells (hNSC). The labeled cells in gel phantoms were detected in MRI and showed decreased relaxation rates in comparison with control. ION with ascorbic acid slightly decreased cell proliferation in comparison with unlabeled cells. Decrease was dependent on nanoparticles concentration. None of the nanoparticle type showed negative effect on cell viability and both demonstrated minor effect on reactive oxygen species (ROS) formation, which was attenuated in the presence of ascorbic acid in medium. Unfortunately, ascorbic acid bound to nanoparticles did not show any effect on ROS attenuation. Cells exposed to both types of nanoparticles showed increased positivity for a phosphorylated form of H2AX a marker of double strand breaks. We showed that ION in low concentrations do not affect cell viability, but have negative effect on cells on DNA level. Their potential use for oxidative stress reduction is dependent on the concentration of ascorbic acid bound to the nanoparticles and this should be further increased.
ACKNOWLEDGEMENTS: This work was supported by the Ministry of Education, Youth and Sports of CR within the LQ1604 National Sustainability Program II (Project BIOCEV-FAR).
The employers shall ensure adequate safety and health protection of the workers. They are obliged to carry out risk assessment and take appropriate measures for risk prevention and control related to all relevant workplace hazards. However, sound risk assessment requires reliable comprehensive information on hazard (toxicity) and exposure which may not be available for many, especially novel, substances and materials, such as nanomaterials (both engineered and accidental). The generally accepted approach used for preliminary risk assessment of nanomaterials is Control banding (CB). CB is a pragmatic tool to manage the risk resulting from exposure to potentially hazardous substances in the absence of firm toxicological and exposure data. Currently, several CB tools have been developed within the international research activities. The aim of this study was to review the CB tools that are presently available for qualitative, semi-quantitative or quantitative estimation of exposure and risk associated with the manufacture and professional use of nanomaterials. The applicability of the various tools was evaluated using two real-life occupational exposure scenarios. Furthemore, the positives, negatives (limitations) of these tools, and the recommendation on their usefulness in particular industrial sectors were analysed.
From the perspective of the immune system, engineered nanoparticles (NPs) represent invading agents. Macrophages are immune cells residing in all organs and tissues as the first line of defense. Interactions of macrophages with NPs can determine fate of NPs as well as their potential toxic effects. Transcriptomics provides a useful tool to get insight into molecular mechanisms underlying these complex interactions and their role in NP toxicity. In this study, we compared toxicity of different types of NPs [NM-100 (TiO2, 110 nm), NM-110 (ZnO, 20 nm), NM-200 (SiO2, 150 nm), NM-300K (Ag, 20 nm)] towards THP-1 macrophage-like cells. Cells were incubated with non-cytotoxic concentrations (1-25 µg/ml) of NPs (determined using the MTS assay) for 24 hours and a microarray technology was used to analyze changes in whole-genome expression. Gene expression profiling revealed substantially different molecular responses following exposure to diverse NPs. While NM-100 did not exhibit any significant effect on the gene expression profile, NM-200 triggered a pro-inflammatory response characterized by activation of the NF-κB transcription factor and induction of numerous chemokines and cytokines. NM-110 and NM-300K also activated genes involved in immune processes, as well as DNA damage response, oxidative stress and modulation of the cell cycle. NM-300K further affected expression of genes related to the apoptotic process. We suppose that higher toxicity of ZnO and Ag NPs leading to DNA damage and apoptosis in THP-1 macrophages is probably caused by extensive intracellular dissolution of these NPs, as supported by TEM imaging. [Supported by MEYS CR (LO1508, LM2015073, LM2015062)].
Nano- and microparticles have always accompanied people in all aspects of their lives. Along with an increasing number of their application, there is also a need for their accurate, fast, and inexpensive size determination. There are numerous techniques, which allow assessment of the particle size, however each of these methods have advantages and limitations. In this study, comparison of several often-used methods for rapid particle size analysis, namely the DCS (differential centrifugal sedimentation), DLS (dynamic light scattering), and SEM (scanning electron microscope), were presented. Especially, the DCS method was carefully evaluated and several parameters influencing the determination of the size distribution were monitored. In the second part of the study, gold nanoparticles were synthesized with a “green” approach and used as a calibration standard for the DCS analysis. It was found that the newly synthesized calibration standards could serve as reliable and stable alternatives to the commercial ones.
The work deals with green synthesis of iron oxides nanoparticles. To prepare these nanoparticles, we used nature extracts, which were made of low cost or waste nature materials.
Nanosilver, in the form of colloidal silver, has been used for many years. In recent years, the development of efficient green chemistry methods for the synthesis of metal nanoparticles by organisms has become a major focus of researchers. The different forms of nanoparticles prepared by phytosynthesis are dependent on the structure as well as the potential reactions of molecules present in plant extracts. These forms of nanoparticles can exhibit antibacterial activity to any bacterial strains. Five types of silver nanoparticles (AgNPs) using inorganic synthesis as well as five types of AgNPs using green synthesis were successfully prepared. The AgNPs generated by inorganic synthesis differed in various concentrations of reducing agent (NaBH4, gallic acid). In addition, the AgNPs prepared by phytosynthesis are easily identified according to the plant extract entering into the synthetic reactions. Extracts of C. sinensis (green tea 1 and 2), T. erecta (Marigold), H. perforatum (St.John’s wort) and A. cepa (onion) were utilised for the phytosynthesis. Inorganically synthesized AgNPs had a higher ability for quenching free radicals. Antibacterial activity was determined on bacterial cultures S. aureus and E. coli. AgNPs synthesized using green tea showed the highest antibacterial activity which was for S. aureus 96 % and for E. coli 95 %. The changes in metabolic pathways were also determined. Silver nanoparticles synthesized using St John’s wort presented the highest numbers of biochemical changes (11 cases) in comparison to control. Disruption of metabolic pathways is a significant discovery which will be interesting to investigate further.
Currently, is the issue of nanoparticles very dynamic and developing scientific research areas. Their positives are indisputable, as evidence by a number of scientific papers and studies. On the other hand, it is very small, as compared with research on nanoparticles, to pay attention to their possible negative consequences, especially from the point of view health risks. In many sectors of human activity (industry, energy, etc.) are nanoparticles released into the environment. The same is true in transport, especially in combustion of fossil fuels with the all negative consequences on the human organism. The paper presents the results of nanoparticles concentration measurement in traffic loaded urban area. There are continuous evaluated measured data from different periods and at different times in relation to traffic intensity at the monitored area. The results of the nanoparticles content confirmed the increased concentration of nanoparticles in relation to traffic intensity.
Road traffic is connected with large volume of fine particles released during brake process of cars. Our research is focused on the phase, structure and chemical analysis of the fine particles taken from some car brake parts by their services. The information on structure and phase composition was obtained by X-Ray Powder Diffraction, Mössbauer Spectroscopy, scanning electron microscopy with EDX and transmission electron microscopy. The results of the wear debris analysis are compared with original brake materials components. Most of recognized particles are based mainly on iron oxides. Wear brake particles are discussed in the relation to the potential risk to the environment and human health.
Friction, i.e., non-combustion processes in traffic can pose a problem for the human health, mainly in terms of exposure to solid particles. During braking, substantial amounts of micron and sub-micron metal based particles are released into the environment. The aim of this pilot study was to evaluate whether these particles could reach the human body via respiratory exposure even through respiratory protective equipment. In this study, workers were exposed to dust particles for one hour during dynamometer maintenance (particle removal and machine cleaning). The particles deposited in the dynamometer were generated during the laboratory tests of the friction process using different types of friction composites. Throughout the course of the work, workers wore respiratory protective equipment to prevent particulates from entering the respiratory tract. These protective devices are used in accordance with EN 140:1998 guidelines for protection against fine dust, water and oil-based liquid aerosols, viruses, bacteria, spores, organic and acid gases, vapors and ozone. A sample of saliva for the detection of trapped particles was analysed using scanning electron microscope and Raman microscope. Quantification of captured particles was performed by inductively coupled plasma atomic emission spectrometer and inductively coupled plasma mass spectrometer. The results show that in the saliva of the workers, particles/agglomerates of metal particles in micron and submicron dimensions were present, with the majority of Al, Fe, Ba, Zn, Cu, Sn, and Bi, which were present in the saliva of the workers even after an hour from the exposure to the friction dust despite wearing respiratory protective equipment.
Wear debris from automotive brake systems represents a major source of non-exhaust emissions from road traffic. Amount of brake wear debris released to the environment increased with numbers of cars. However, their impact on the environment and human health is still unknown. One of the ways how to evaluate their potential environmental impact is testing the acute aquatic toxicity on freshwater green algae.
Aim of this study is evaluation of the acute aquatic toxicity of airborne brake wear debris particles on freshwater green algae Raphidocelis subcapitata. Elemental composition of collected brake wear debris after standard dynamometer test was analyzed by scanning electron microscopy and X-ray fluorescence analysis and phase composition was determined by X-ray powder diffraction analysis. Particle size distribution was characterized, as well. Airborne brake wear debris contains particles in the range values from 3.98 µm (d10) to the 75.18 µm (d90) and its composition is mostly based on amorphous carbon and iron. Accumulation of these elements and compounds in the environment may pose risk to the water environment. The fifty percent effective concentration (EC50) was determined for the concentration 50.05 g/l of airborne brake wear debris to freshwater green algae Raphidocelis subcapitata.
Increasing production of nanomaterials leads to their increased presence in the environment. The impact of their exposure to plants, their uptake and distribution in the plant body are, however, yet generally unknown. In this study, samples of moss Pleurozium schreberi Brid. Mitt. were gathered, treated in various ways common in biomonitoring surveys under laboratory conditions and exposed to ZnO nanoparticles for five weeks, twice a week. Sequential elution technique was then employed in order to determine the distribution of Zn in the thalli – adhering to the surface, in the extracellular, intracellular, and particulate fractions. Cell membrane disruption was evaluated by simultaneously determining the inside/outside the cell potassium concentration ratio. All the treatments affected both the Zn distribution and the cell membrane integrity to some extent. However, in order to accurately determine the distribution of the accumulated metal reflecting the environmental exposure to nanoparticles, to avoid irrigation prior to the exposure as well as oven-drying of the samples is hereby recommended.
Monitoring of migration of engineered nanoparticles (NPs) used for groundwater remediation is a challenging task regarding their unambiguous identification and quantification in sediments. Particularly distinguishing between iron NPs and naturally occurring Fe colloids requires a special effort. When employing inductively coupled plasma mass spectrometry (ICP-MS) for NPs analysis based on trace elements, there is a need for set of representative background samples. One of the possibilities how to cope with this demand is to determine the ratios of elements typical for NPs and environment where they were applied.
In our work we established a novel approach to the tracing of iron NPs in the environment based on multielement fingerprint ICP-MS analysis. Lanthanides appear to be one of the possible groups of elements suitable for this purpose as well as other trace elements naturally occurring in environment and constituting the NPs. The multielemental inorganic analysis of different engineered NPs used within the FP7 NANOREM project was done and their fingerprints were compared with the profiles of groundwater/sediment samples from the localities before/after the remediation. The method could be a good alternative to the ex-situ measurements of total and dissolved iron, especially in the case of long-term monitoring of the wells in the greater distance from the injection points.
Carbon dots (CDs) are very popular type of nanomaterial for bio-application because of their excellent fluorescent properties, biocompatibility and biodegradability. In our previous study, we firstly found out penetration of non-modified positively charged carbon dots into the nucleus of mouse fibroblasts NIH/3T3. Therefore, in this work, we focused on deeper study of CDs distribution inside cells especially in the cell nucleus by fluorescence microspectroscopy. The results showed, that intranuclear environment affects fluorescent properties and can evoke fluorescence shifts, change CDs size and interact with the main antioxidant – glutathione. Moreover, time penetration of CDs across plasma cell membrane was recorded and cytotoxicity evaluated. Advanced information about behaving of nanomaterials in the cell nucleus and nucleolus is very important for future understanding of intracellular mechanisms.
The tremendous increase of the use of nanomaterials (NMs) has been witnessed during the last decade in many areas of human life including chemical industry, cosmetics, biomedicine or food technology. The variety of NMs, their unique properties, almost ubiquitous presence and the size range of 1-100 nm raised the interest of toxicologists. The evaluation of the frequency of micronuclei (MN) as a result of the genotoxic events is a broadly utilized and well established approach in in vitro studies for testing the risk of chemicals exposure. Nevertheless, properties of the NMs give rise to the questions concerning the optimal methodological variants of the MN assay.
In our study, five types of well characterized NMs (TiO2: NM-101 and NM-103; SiO2: NM-200; Ag: NM-300K and NM-302) of specific size, shape, or e.g. dimensions of aggregates were involved in the genotoxicity testing using four variants of protocols differing in the time of NM exposure, application of cytochalasin-B combined with simultaneous and delayed co-treatment with NPs.
Our preliminary data showed the evidence of the transport of NPs into the cells and their intracellular aggregation when tests without cytochalasin-B were performed. While no significant increase in the frequency of MN after simultaneous exposure to NPs and cytochalasin-B was observed, delayed co-treatment with some NPs increased the frequency of MN.
This work was supported by the grant of the Ministry of Education Youth and Sports CR #LO1508.
Toxicity of TiO2 nanomaterials (NMs) depends on properties such as nanomaterial shape, size, crystal structure, zeta potential, aggregation and agglomeration tendency, surface characteristics and coatings. However, their effect on toxicity remains unclear due to ambiguous results reported by different studies. The present study examined the cytotoxic effect of fourteen diverse NMs TiO2 without photoactivation in human monocytic cells THP-1 differentiated into macrophage-like cells.
A set of NMs consists of 5 variants of anatase and 5 variants of rutile nanoparticles differing in their diameter (from 3 to 165 nm), and 3 variants of high aspect ratio anatase nanofibers. All TiO2 samples were characterized in the powder form and dispersed in water and cell culture media. Three cytotoxicity assays were used: MTS, WST 1, and LDH. For all nanomaterials, three independent repetitions were carried out.
Overall, cytotoxicity of all NMs was low even at the highest concentration of 256 µg/ml. The viability did not decrease below 60% for WST-1 and MTS assays and 80% for the LDH assay. Besides concentration, polydispersity index was identified as the most important cytotoxic factor. Clear nonlinear relationship between crystalline size and cytotoxicity was detected; higher toxicity induced NMs within the size range of 20-60 nm. Increase cytotoxicity in the given diameter size range would give an answer to inconsistent findings at size and cytotoxicity relationship.
The authors acknowledge the assistance provided by the Research Infrastructure NanoEnviCz and NANOGEN, supported by the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic under projects No. LM2015073 and No. LO1508, and CENATOX (GACR P503/12/G147).
Easy scale up of production led to an increase in cosmetic industry interest in lipid nanostructures. There are currently some liposome formulations on the market and the amount of these products will indoubtedly continue to grow. For this, detailed studies about their potential genotoxicity and cytotoxicity are neccesary.
Presented work deals with preparation and characterization of liposome particles with aqueous and oil extracts of plant origin. The aim of this work was to observe cytotoxic and genotoxic effects of prepared liposomes.
Total phenolics, flavonoids and antioxidant activity of plant extracts were determined using spectrophotometry as well as encapsulation efficiency. Stability of liposome particles was evaluated using zeta potential and size of liposomes was determined by dynamic light scattering. Potential genotoxic effects of liposomes were analysed using SOS Chromotest. Cytotoxicity of liposome particles was observed in human epidermal keratinocytes HEK (102-05a).
Micro- and nanoparticles with encapsulated antioxidant and antimicrobial active compounds can enhance the effectiveness of cosmetics and pharmaceuticals. In this work, the potential use of liposome particles with natural plant extracts in appropriate concentration was proposed.
ACKNOWLEDGEMENTS: This work was also supported by the project “Materials Research Centre at FCH BUT—Sustainability
and Development” no. LO1211 of the Ministry of Education, Youth and Sports of the Czech Republic.
The article describes the preparation of samarium oxide nanoparticles (nano Sm2O3) via thermal decomposition of a transient complex formed in situ from Sm(NO3)3·6H2O and glycine and its acute aquatic toxicity to Chlorella vulgaris. The resulting nanoparticles were characterized by X-ray powder diffraction analysis, which showed the samarium oxide nanoparticles to be with the crystallite size of 11 nm. Morphology of the samarium oxide nanoparticles was examined by scanning and transmission electron microscopy. Electron diffraction observed in transmission electron microscopy corresponds to the results obtained from X-ray diffraction analysis. The elemental composition of the product was confirmed by EDS analysis. Freshwater green algae (Chlorella vulgaris) served as a model organism for evaluation of acute aquatic toxicity. Effective concentration of toxicity EC50 was determined for the concentration of 2.43 g·dm-3 of samarium oxide nanoparticles to the freshwater green algae strain.
Toxicity of any substance is determined by its physico-chemical properties and tissue exposure. In the case of nanoparticles (NPs), the relevant properties include the size, aspect ratio, surface charge, chemical composition etc.; the tissue exposure represents the NPs’ concentration and exposure duration. Thus, any adverse response observed in a living organism is related to delivered dose (that is, NPs amount in the target tissue) rather than to the total dose administered. The HISENTS project aims to develop a platform of integrated modules for nanotoxicity screening. The PBPK model is an integral part of the platform as it provides information on tissue exposure to nanomaterials via their ADME (absorption, distribution, metabolism, and excretion) behavior. For this reason, a simple perfusion rate-limited PBPK model requiring only one NP-specific parameter per tissue was built. The model treats all tissues as well-stirred compartments and the rate of NP exchange is only limited by the tissue perfusion. The model was calibrated against in vivo data for nano-titania [1] and, despite its simplicity, gave a reasonable agreement between predicted and measured NPs concentrations in the tissues. The main advantage of the model is that the biodistribution of NPs is described using only thermodynamic parameters (partition coefficients) which can be estimated from equilibrium responses of the individual modules. ACKNOWLEDGEMENTS: This work is financed by the project No. H2020-NMP-685817 High level Integrated SEnsor for NanoToxicity Screening (HISENTS). REFERENCE: [1] G. Xie, C. Wang, J. Sun, G. Zhong G. Toxicol. Lett. 205 (2011) 55–61.
Applications of fullerene water solutions (FWS) in medicine and cosmetics are of current interest due to their antioxidant, antitumor and antibacterial properties. However, up to now there is no consensus to the question about influence of these systems in living organisms. In the literature both positive and negative health influences have been reported depending on the type of primary organic solvents used in the technique preparation and the cluster size distribution in the final solutions, as well as on the chemical modification of fullerenes resulting in a wide class of biologically active derivatives. In particular, there are indications that cytotoxicity and antibacterial properties of FWS correlate with the aggregate formation. The latter also has an impact on the environment, since after utilization the FWS interacting with natural salts coagulate, which significantly complicates their removal. The given report presents results of complex structural characterization, toxicity and efficiency in antitumor therapy for various types of fullerenes C60 and C70 aqueous solutions, and also their complexes with anticancer drugs. Correlation of structure with biological properties of studied fullerenes systems is analyzed.