Carbon nanotubes focus the attention of many scientists because of their huge potential of industrial applications, but there is a paucity of information on the toxicological properties of this material. The aim of this experimental study was to characterize the biological reactivity of purified multi-wall carbon nanotubes in the rat lung and in vitro. Multi-wall carbon nanotubes (CNT) or ground CNT were administered intratracheally (0.5, 2 or 5 mg) to Sprague-Dawley rats and we estimated lung persistence, inflammation and fibrosis biochemically and histologically. CNT and ground CNT were still present in the lung after 60 days (80% and 40% of the lowest dose) and both induced inflammatory and fibrotic reactions. At 2 months, pulmonary lesions induced by CNT were characterized by the formation of collagen-rich granulomas protruding in the bronchial lumen, in association with alveolitis in the surrounding tissues. These lesions were caused by the accumulation of large CNT agglomerates in the airways. Ground CNT were better dispersed in the lung parenchyma and also induced inflammatory and fibrotic responses. Both CNT and ground CNT stimulated the production of TNF-alpha in the lung of treated animals. In vitro, ground CNT induced the overproduction of TNF-alpha by macrophages. These results suggest that carbon nanotubes are potentially toxic to humans and that strict industrial hygiene measures should to be taken to limit exposure during their manipulation.
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http://dx.doi.org/10.1016/j.taap.2005.01.008 | DOI Listing |
ACS Nano
January 2025
Nano Hybrid Technology Research Center, Korea Electrotechnology Research Institute (KERI), Changwon 51543, Republic of Korea.
Hydrogen-bond-driven 1D assembly of carbon nanotubes dispersed in organic solvents remains challenging owing to difficulties associated with achieving high oxidation levels and uniform dispersion. Here, we introduced a bioinspired wet-spinning method that utilizes highly oxidized single-walled carbon nanotubes dispersed in organic solvents without superacid or dispersants. By incorporating submicrometer-sized graphene oxide nanosheets, we facilitated the ejection of 1.
View Article and Find Full Text PDFSmall
January 2025
College of Materials Science and Engineering, Sichuan University, Chengdu, 610065, China.
The transition metal single atoms (SAs)-based catalysts with M-N coordination environment have shown excellent performance in electrocatalytic reduction of CO, and they have received extensive attention in recent years. However, the presence of SAs makes it very difficult to efficiently improve the coordination environment. In this paper, a method of direct high-temperature pyrolysis carbonization of ZIF-8 adsorbed with Ni and Fe ions is reported for the synthesis of Ni SAs and FeN nanoparticles (NPs) supported by the N-doped carbon (NC) hollow nanododecahedras (HNDs) with nanotubes (NTs) on the surface (Ni SAs/FeN NPs@NC-HNDs-NTs).
View Article and Find Full Text PDFAnalyst
January 2025
Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu Province 215123, China.
The choices of matrices and protocols for sample deposition are critical factors, which impact each other in the matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI). Previous reports on MALDI MS matrices have only compared their performances in terms of their MS signal intensities and provided optical microphotos or MALDI MS images of sample spots but typically lacked quantitative evaluation. Therefore, there is an urgent need to develop a multivariate model to evaluate the performance of different combinations of matrices and sample protocols.
View Article and Find Full Text PDFSmall
January 2025
Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
Establishing the relationship between catalytic performance and material structure is crucial for developing design principles for highly active catalysts. Herein, a type of perovskite fluoride, NHMnF, which owns strong-field coordination including fluorine and ammonia, is in situ grown on carbon nanotubes (CNTs) and used as a model structure to study and improve the intrinsic catalytic activity through heteroatom doping strategies. This approach optimizes spin-dependent orbital interactions to alter the charge transfer between the catalyst and reactants.
View Article and Find Full Text PDFSe Pu
February 2025
College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing 102249, China.
Trace contaminants are toxic and their widespread presence in the environment potentially threatens human health. The levels of these pollutants are often difficult to determine directly using instruments owing to the complexities of environment matrices. Hence, pretreatment steps, such as sample purification and concentration, are key along with various processes that enhance the accuracy and sensitivity of the detection method.
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