Carbon Black Nanomaterials Research Articles

Reliable assessment of carbon black nanomaterial of a variety of cell culture media for in vitro toxicity assays by asymmetrical flow field-flow fractionation

Carbon black nanomaterial (CB-NM), as an industrial product with a large number of applications, poses a high risk of exposure, and its impact on health needs to be assessed. The most common testing platform for engineered (E)NMs is in vitro toxicity assessment, which requires prior ENM dispersion, stabilization, and characterization in cell culture media. Here, asymmetric flow field-flow fractionation (AF4) coupled to UV–Vis and dynamic light scattering (DLS) detectors in series was used for the study of CB dispersions in cell culture media, optimizing instrumental variables and working conditions. It was possible to disperse CB in a non-ionic surfactant aqueous solution due to the steric effect provided by surfactant molecules attached on the CB surface which prevented agglomeration. The protection provided by the surfactant or by culture media alone was insufficient to ensure good dispersion stability needed for carrying out in vitro toxicity studies. On the other hand, cell culture media in combination with the surfactant improved dispersion stability considerably, enabling the generation of shorter particles and a more favourable zeta potential magnitude, leading to greater stability due to electrostatic repulsion. It was demonstrated that the presence of amino acids in the culture media improved the monodisperse nature and stability of the CB dispersions, and resulted in a turn towards more negative zeta potential values when the pH was above the amino acid isoelectric point (IEP). Culture media used in real cell culture scenarios were also tested, and in vitro toxicity assays were developed optimizing the compatible amount of surfactant.Graphical abstract

Enhancing Cotton Fabrics Properties by Coating with Zinc Oxide and Carbon Black Nanomaterials and Dyeing with Terminalia catappa Leaves Powder

This research focused on thermal stability, color fastness and UV protection properties enhancing cotton fabric coated with ZnO and carbon black nanoparticles and dyed with Terminalia catappa leaves powder. The XRD patterns of ZnO nanoparticles contained peaks associated with the hexagonal system, which can be attributed to the structure of ZnO wurtzite. The XRD pattern of carbon black showed a typical amorphous structure. SEM images of the coated cotton surface revealed a scattering of carbon and zinc oxide nanoparticles that increases in size in relation to the amount of carbon and zinc nanoparticles. The ATR-FT-IR spectra of cotton coated with ZnO and carbon revealed the presence of O-H bond, H-C-H bond, C-O-C bond, C-O bond and Zn-O bond. TGA analysis revealed that the cotton coated with zinc oxide and carbon exhibited a greater than 100 °C heat resistance. TGA analysis of cotton coated with CZ4 nanoparticles at 352 °C revealed a weight loss of 70.61%, whereas uncoated cotton lost 85.96 percent of its weight at 358 °C. Light fastness and washing fastness properties of cotton coated with zinc oxide and carbon nanoparticles were 4–5 (good to very good). The FE-SEM and EDS elemental analyses were used to confirm residual elements affected by the excellent UV protective functions of the coated cotton. Cotton fabrics coated with Zn3 and CZn4 are the optimal condition for enhancing the thermal stability, washability, and UV protection of dyed cotton. After 30 wash cycles, the EDS analysis revealed that the cotton fabrics coated with Zn3 and CZn4 retained their durability, with Zn element concentrations of 66.62 (%W) and 67.60 (%W), respectively. The coated cotton significantly outperforms uncoated cotton in terms of thermal stability, color fastness, UV blocking, tensile strength, and air permeability. As the results of this research established; the optimal dyeing protocol for cotton to obtain the desired textile properties.

Characterization and Quantitation of Carbon Black Nanomaterials in Polymeric and Biological Aqueous Dispersants by Asymmetrical Flow Field Flow Fractionation.

Characterization of carbon black (CB) nanomaterials is required in industrial and research areas. Hence, in this study, asymmetrical flow field flow fractionation coupled to UV–vis and DLS detectors in series (AF4-UV–vis-DLS) was studied to evaluate the CB dispersion behavior in polymeric and biological dispersants, given the relevance of these media in practical applications. Under the experimental conditions, the results indicated that polymeric and biological dispersions showed size distributions with hydrodynamic diameters of 404 and 175 nm, respectively, for a particle core diameter of 40 nm. The polymeric dispersant provided lower stability as a function of time than that achieved by the biological dispersant. AF4 allowed separation of different core-sized CB (40, 69, and 72 nm) according to their hydrodynamic size using cross-flow rates of 0.5 mL·min–1 and 1 mL·min–1 for polymeric and biological dispersants, respectively. The dilution of the polymeric dispersion with different real water matrices produced a dramatic loss of dispersion stability, this effect being negligible in the case of biological dispersions.

Single-atom doping in carbon black nanomaterials for photothermal antibacterial applications

The growing problem of antimicrobial resistance has become a serious threat to human health. Loading single atoms onto carbon-based materials is a new strategy to develop environmentally friendly and stable photothermal antibacterial nanomaterials. We report the successful synthesis of carbon black nanomaterials doped with copper single atoms, nickel single atoms, and gold single atoms of similar mass concentration guided by theoretical calculations. The introduction of metal single atoms fundamentally changed the electronic structure of the original carbon black and resulted in high photothermal properties and antibacterial activity. Among these antimicrobial materials, the copper-doped material is more active than the other two, which is consistent with our theoretical calculations. Also, the combination of theoretical calculations and experimental validation suggests an intrinsic mechanism of bactericidal activity. This strategy has the potential to be extended to other single-atom doped systems with improved photothermal properties. • Demonstration that metal single atoms can improve photothermal antibacterial properties • Design of metal-single-atom-loaded materials is guided by theoretical calculations • Synthetic carbon-based materials are low cost, biocompatible, and NIR responsible Yang et al. develop low-cost carbon black nanomaterials loaded with metal single atoms for photothermal antimicrobial applications. Guided by theoretical calculations, metal single atoms are employed to modulate the electronic structure of carbon black. As predicted, the photothermal performance is substantially improved and highly dependent on the metal element.

Doping white carbon black particles to adjust the electro-opticical properties of PDLC

ABSTRACT Polymer-dispersed liquid crystal (PDLC) is a possible active matrix transparent display technology due to its high transparency, good visibility, and low-power consumption. This paper examined the morphology of polymer-dispersed liquid-crystal materials (PDLCs), which show great potential for display applications. The materials were blends of an eutectic nematic liquid-crystal mixture and a UV-cross-linkable polymeric matrix. White carbon black nanomaterials with high surface adsorbability, high purity, and good stability are ideal materials for the driver circuit of the PDLC display. The influence of the ratio between polymerised monomers and between polymerised monomers and liquid crystals on the electro-optical properties of PDLC system had been studied. We explored the doping of white carbon black nanomaterials in the liquid crystal polymer systems. To achieve this, we have taken advantage of the liquid crystal electro-optical effect experimental instrument to study a series of electro-optical parameters of PDLC, using also additional information on the nanodroplet size and shape distribution provided by SEM images of the PDLC cross-section.

A dual electro-optical biosensor based on Chlamydomonas reinhardtii immobilised on paper-based nanomodified screen-printed electrodes for herbicide monitoring

The indiscriminate use of herbicides in agriculture contributes to soil and water pollution, with important endangering consequences on the ecosystems. Among the available analytical systems, algal biosensors have demonstrated to be valid tools thanks to their high sensitivity, cost-effectiveness, and eco-design. Herein, we report the development of a dual electro-optical biosensor for herbicide monitoring, based on Chlamydomonas reinhardtii whole cells immobilised on paper-based screen-printed electrodes modified with carbon black nanomaterials. To this aim, a systematic study was performed for the selection and characterisation of a collection among 28 different genetic variants of the alga with difference response behaviour towards diverse herbicide classes. Thus, CC125 strain was exploited as case study for the study of the analytical parameters. The biosensor was tested in standard solutions and real samples, providing high sensitivity (detection limit in the pico/nanomolar), high repeatability (RSD of 5% with n = 100), long lasting working (10 h) and storage stability (3 weeks), any interference in the presence of heavy metals and insecticides, and low matrix effect in drinking water and moderate effect in surface one.

Magnetic beads combined with carbon black-based screen-printed electrodes for COVID-19: A reliable and miniaturized electrochemical immunosensor for SARS-CoV-2 detection in saliva

The diffusion of novel SARS-CoV-2 coronavirus over the world generated COVID-19 pandemic event as reported by World Health Organization on March 2020. The huge issue is the high infectivity and the absence of vaccine and customised drugs allowing for hard management of this outbreak, thus a rapid and on site analysis is a need to contain the spread of COVID-19. Herein, we developed an electrochemical immunoassay for rapid and smart detection of SARS-CoV-2 coronavirus in saliva. The electrochemical assay was conceived for Spike (S) protein or Nucleocapsid (N) protein detection using magnetic beads as support of immunological chain and secondary antibody with alkaline phosphatase as immunological label. The enzymatic by-product 1-naphtol was detected using screen-printed electrodes modified with carbon black nanomaterial. The analytical features of the electrochemical immunoassay were evaluated using the standard solution of S and N protein in buffer solution and untreated saliva with a detection limit equal to 19 ng/mL and 8 ng/mL in untreated saliva, respectively for S and N protein. Its effectiveness was assessed using cultured virus in biosafety level 3 and in saliva clinical samples comparing the data using the nasopharyngeal swab specimens tested with Real-Time PCR. The agreement of the data, the low detection limit achieved, the rapid analysis (30 min), the miniaturization, and portability of the instrument combined with the easiness to use and no-invasive sampling, confer to this analytical tool high potentiality for market entry as the first highly sensitive electrochemical immunoassay for SARS-CoV-2 detection in untreated saliva.

Developmental toxicity of carbon nanoparticles during embryogenesis in chicken

Nanoparticles (NPs) are very small particles present in a wide range of materials. There is a dearth of knowledge regarding their potential secondary effects on the health of living organisms and the environment. Increasing research attention, however, has been directed toward determining the effects on humans exposed to NPs in the environment. Although the majority of studies focus on adult animals or populations, embryos of various species are considered more susceptible to environmental effects and pollutants. Hence, research studies dealing mainly with the impacts of NPs on embryogenesis have emerged recently, as this has become a major concern. Chicken embryos occupy a special place among animal models used in toxicity and developmental investigations and have also contributed significantly to the fields of genetics, virology, immunology, cell biology, and cancer. Their rapid development and easy accessibility for experimental observance and manipulation are just a few of the advantages that have made them the vertebrate model of choice for more than two millennia. The early stages of chicken embryogenesis, which are characterized by rapid embryonic growth, provide a sensitive model for studying the possible toxic effects on organ development, body weight, and oxidative stress. The objective of this review was to evaluate the toxicity of various types of carbon black nanomaterials administered at the beginning of embryogenesis in a chicken embryo model. In addition, the effects of diamond and graphene NPs and carbon nanotubes are reviewed.

Carbon black-based disposable sensor for an on-site detection of free chlorine in swimming pool water

Chlorine is the most common chemical compound used for treatment of water at ppm levels, although at higher concentration it can generate harmful disinfection by-products. To easily monitor the correct level of free chlorine, cost-effective and miniaturized devices for fast and on-site detection are required. Herein, we report the development of a novel miniaturized and cost-effective screen-printed electrode modified with carbon black nanomaterial for an effective amperometric detection of free chlorine in swimming pool water. The carbon black was used as working electrode modifier for chlorine quantification at low applied potential, overcoming the fouling problem. In addition, the use of stable and cost-effective carbon black dispersion allows for a mass-production of the modified sensor by an automatable drop casting method. This sensor has demonstrated the capability to detect free chlorine in a linear range of 0.05–200 ppm with a detection limit of 0.01 ppm in standard solution as well as in swimming pool water. The achieved results demonstrated for the first time the suitability of the carbon black as electrode nanomodifier for free chlorine detection, and the possibility to produce a miniaturized and cost-effective carbon black-based printed sensor for reliable free chlorine quantification in water samples.

No chronic effects on biochemical biomarkers, feeding and survival of carnolian honeybees (Apis mellifera carnica) after exposure to nanosized carbon black and titanium dioxide

Honeybees (Apis mellifera) are important pollinators threatened by environmental pollution, plan protection products and other potential contaminants. Due to an extensive predicted use of engineered nanomaterials (NMs) in agriculture the impact on honeybees should be investigated. We studied the 10-days chronic dietary effect of carbon black (CB) and titanium dioxide (TiO2) NMs on the antioxidant activities, cholinergic function, feeding behaviour and survival of honeybees. Exposure of honeybees Apis mellifera carnica to TiO2 and CB NMs (1 mg ml-1) did not affect the feeding and survival. No alteration of catalase, acetylcholinesterase and glutathione S-transferase enzymatic activity was noticed in the brain of honeybees, indicating that TiO2 and CB NMs at the tested exposure dose had no adverse effects on honeybees. Currently predicted environmental concentrations for TiO2 and CB NMs are significantly lower than the concentration tested in the current study. Based on our findings we conclude that the potential use of TiO2 and CB NMs in agriculture is currently safe for honeybees at the tested concentration level and presents potential advantages compared to other NMs with known toxic potential.

Effect of carbon black nanomaterial on biological membranes revealed by shape of human erythrocytes, platelets and phospholipid vesicles.

BackgroundWe studied the effect of carbon black (CB) agglomerated nanomaterial on biological membranes as revealed by shapes of human erythrocytes, platelets and giant phospholipid vesicles. Diluted human blood was incubated with CB nanomaterial and observed by different microscopic techniques. Giant unilamellar phospholipid vesicles (GUVs) created by electroformation were incubated with CB nanomaterial and observed by optical microscopy. Populations of erythrocytes and GUVs were analyzed: the effect of CB nanomaterial was assessed by the average number and distribution of erythrocyte shape types (discocytes, echinocytes, stomatocytes) and of vesicles in test suspensions, with respect to control suspensions. Ensembles of representative images were created and analyzed using computer aided image processing and statistical methods. In a population study, blood of 14 healthy human donors was incubated with CB nanomaterial. Blood cell parameters (concentration of different cell types, their volumes and distributions) were assessed.ResultsWe found that CB nanomaterial formed micrometer-sized agglomerates in citrated and phosphate buffered saline, in diluted blood and in blood plasma. These agglomerates interacted with erythrocyte membranes but did not affect erythrocyte shape locally or globally. CB nanomaterial agglomerates were found to mediate attractive interaction between blood cells and to present seeds for formation of agglomerate - blood cells complexes. Distortion of disc shape of resting platelets due to incubation with CB nanomaterial was not observed. CB nanomaterial induced bursting of GUVs while the shape of the remaining vesicles was on the average more elongated than in control suspension, indicating indirect osmotic effects of CB nanomaterial.ConclusionsCB nanomaterial interacts with membranes of blood cells but does not have a direct effect on local or global membrane shape in physiological in vitro conditions. Blood cells and GUVs are convenient and ethically acceptable methods for the study of effects of various substances on biological membranes and therefrom derived effects on organisms.

Semi-automatic size measurement of primary particles in aggregated nanomaterials by transmission electron microscopy

A combination of transmission electron microscopic imaging and semi-automatic image analysis allows detecting and measuring the primary particles of aggregated nanomaterials. The median primary particle size, the number based size distribution, the percentage of nanoparticles and the volume specific surface area of powdered nanomaterials are determined in the framework of the European Commission's nanomaterial definition.The principle of a semi-automated approach to measure the minimal size in one dimension of primary particles in aggregates by transmission electron microscopy is developed using the model of the powdered, aggregated titanium dioxide representative test nanomaterial NM-100 with a mean primary particle diameter near the 100nm limit. The primary particles are detected based on watershed segmentation and their minimal size and overlap coefficient are measured based on an Euclidean distance map. The primary particles of NM-100 contain 22% nanoparticles, with a size between 1nm and 100nm. The method is evaluated to measure other aggregated TiO2, synthetic amorphous silica and carbon black nanomaterials for which the percentage of nanoparticles is nearly 100%. A high level of automation allows measuring the diameter of the maximal inscribed circle efficiently. The maximal inscribed circle is a measure for the minimal primary particle size in one dimension and is shown to be commutable with Feret min measurements. The standard method to determine the fractal properties and the volume specific surface area of fractal-like aggregates is refined supporting on the diameter of the maximal inscribed circle and the overlap coefficient measurements for each individual primary particle.

Electroanalytical Characterization of Carbon Black Nanomaterial Paste Electrode: Development of Highly Sensitive Tyrosinase Biosensor for Catechol Detection

In this work, the electrochemical behavior of carbon black paste electrode prepared using a nanostructured commercial carbon black (N220) was investigated. The sensor was challenged with several potentially interesting analytes by means of cyclic voltammetry technique and the results compared with graphite carbon paste electrode. Shifting in peak potential and/or increase in the peak currents for some analytes such as ferricyanide, ascorbic acid, acetoaminophen, epinephrine, and DOPAC were observed. The carbon black paste was combined with tyrosinase enzyme to produce a biosensor which was challenged in amperometric mode with catechol. The highest sensitivity, equal to 625 nA/μM, coupled with lowest detection limit of 0.008 μM was observed for this formulation relative to those made with graphite and even when compared with carbon nanotubes tyrosinase paste electrode previously reported. In this way, the carbon black could be considered a good electrode material for constructing other electrochemical biosensors with the advantage to be a nanostrutured material at low cost.

High performance electrochemical sensor based on modified screen-printed electrodes with cost-effective dispersion of nanostructured carbon black

Abstract A novel sensor based on a screen-printed electrode (SPE) modified with a stable dispersion of commercially available carbon black (CB) N220 was developed. This probe showed significantly enhanced electrochemical activity relative to a bare SPE when tested with ferricyanide, epinephrine, norepinephrine, benzoquinone and NADH. When challenged in amperometric batch mode with NADH, the response was stable and revealed a linear dependence up to 2·10−4 mol L−1 with a detection limit of 3·10−7 mol L−1. The analytical performance, coupled with the low cost of the CB nanomaterial, suggests that this sensor holds promise for electrochemical applications.

Carcinogenicity of inhaled nanoparticles

Large epidemiological studies in the United States have shown a statistical association between air concentration of the fine dust fraction PM2.5 in the general environment and increased risk of lung cancer. A quantitative risk assessment for lung cancer based on these studies corresponds to risk estimates based on studies at workplaces with exposure to diesel engine emissions; its magnitude cannot be explained by the known carcinogenicity of organic substances or metals adsorbed to the insoluble particle core. Carcinogenic effects of diesel particles were observed after inhalation in rats independently in several studies. The surprisingly strong effect of diesel particles was partially attributed to their small size. This hypothesis was corroborated by inhalation studies with synthetic nanoparticles virtually free of organic compounds. IARC found sufficient evidence for the carcinogenicity of carbon black and of titanium dioxide in experimental animals. Long-term studies by the method of intratracheal instillation confirmed the carcinogenic effects in rats for an even broader spectrum of synthetic nanoparticles. Non-positive studies with hamsters are not valid because hamsters did not develop lung tumors after inhalation of some known human carcinogens. In recent years, the number of publications reporting in vitro genotoxicity of TiO2 and of carbon black nanomaterials has increased. Overall, there is clear positive evidence for carcinogenicity in rats, together with supporting evidence from human data of structurally related substances. Therefore, the European Union (EU) criteria for category 2 of carcinogenic substances appear to be fulfilled for bio-durable nanoparticles consisting of matter without known significant specific toxicity.