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Environmental Science and Pollution... Feb 2023Physicochemical properties of nanoparticles are important in regulating nanoparticle toxicity; however, the contribution of nanoparticle charge remains unclear. The...
Physicochemical properties of nanoparticles are important in regulating nanoparticle toxicity; however, the contribution of nanoparticle charge remains unclear. The objective of this study was to investigate the pulmonary effects of inhalation of charged soot nanoparticles. We established a stably charged nanoparticle generation system for whole-body exposure in BALB/c mice, which produced positively charged, negatively charged, and neutral soot nanoparticles in a wide range of concentrations. After a 7-day exposure, pulmonary toxicity was assessed, together with proteomics analysis. The charged soot nanoparticles on average carried 1.17-1.35 electric charges, and the sizes for nanoparticles under different charging conditions were all fixed at 69 ~ 72 nm. We observed that charged soot nanoparticles induced cytotoxic LDH and increased lung permeability, with the release of 8-isoprostane and caspase-3 and systemic IL-6 in mice, especially for positively charged soot nanoparticles. Next, we observed that positive-charged soot nanoparticles upregulated Eif2, Eif4, sirtuin, mammalian target of rapamycin (mTOR), peroxisome proliferator-activated receptors (PPAR), and HIPPO-related signaling pathways in the lungs compared with negatively charged soot nanoparticles. HIF1α, sirt1, E-cadherin, and Yap were increased in mice's lungs by positively charged soot nanoparticle exposure. In conclusion, carbonaceous nanoparticles carrying electric ions, especially positive-charged, are particularly toxic when inhaled and should be of concern in terms of pulmonary health protection.
Topics: Animals; Mice; Soot; Lung; Nanoparticles; Administration, Inhalation; Mammals
PubMed: 36223019
DOI: 10.1007/s11356-022-23444-4 -
Analytical Chemistry Nov 2022Soot, mainly derived from incomplete combustion of fossil fuel and biomass, exists ubiquitously in different environmental matrixes. To study the detrimental effects of...
Soot, mainly derived from incomplete combustion of fossil fuel and biomass, exists ubiquitously in different environmental matrixes. To study the detrimental effects of soot on climate, air quality, and human health, accurate quantification of soot is an important prerequisite. However, until now, quantification of soot in environmental media, especially in carbonaceous media, is still very challenging. Here, we report a matrix-free laser desorption/ionization mass spectrometry (LDI-MS) method for in situ imaging of soot particles in size-segregated aerosol samples collected on filter membranes. A series of round-shaped sample spots in filter membranes were selected and subjected to MS imaging analysis, enabling direct in situ quantification of soot without solvent extraction or separation. Especially, the MS imaging with serial sample spots can overcome the problems of sweet-spot in LDI-MS and inhomogeneous distribution of soot in the filter membrane, thus greatly improving the precision of quantification. The limit of detection of soot was 4 ng/m and the recovery was 84.4-126%. By using this method, we found that a higher soot content was present in larger-sized particulate matter than smaller-sized particles, suggesting that aerosol soot was mainly derived from primary emission sources. Furthermore, this method also shows the potential to analyze nitrate and sulfate species in PM. To the best of our knowledge, it is the first method capable of simultaneous analysis of inorganic salts and soot in air samples. It represents a novel strategy for in situ quantification of aerosol soot with the advantages of high specificity, high sensitivity, separation-, solvent- and matrix-free.
Topics: Humans; Soot; Air Pollutants; Particulate Matter; Aerosols; Mass Spectrometry; Solvents; Carbon; Environmental Monitoring
PubMed: 36301736
DOI: 10.1021/acs.analchem.2c01443 -
Journal of Environmental Sciences... Oct 2018Oxygenated fuel represents an attractive alternative as an additive for reducing soot emissions. Dimethyl carbonate (DMC) is an oxygenated compound which is a good...
Oxygenated fuel represents an attractive alternative as an additive for reducing soot emissions. Dimethyl carbonate (DMC) is an oxygenated compound which is a good option to reduce soot, but the detailed characteristics of soot produced from combustion of hydrocarbon fuels blended with DMC are still lacking. The present research studied the nanostructure and reactivity of soot particles in ethylene/DMC normal and inverse diffusion flames. High resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to analyze the nanostructure and reactivity of soot. It was found that DMC addition was effective in decreasing the average weights of soot formed in flames. The results of HRTEM images showed that soot particles obtained with DMC addition showed liquid-like material and tight bonding, and exhibited more highly disorganized layers, which give it higher reactivity than soot obtained without DMC addition. Furthermore, HRTEM was used to analyze soot fringe characteristics consisting of fringe tortuosity, fringe length, and fringe separation. XRD was used to crosscheck the results for fringe separation, and was consistent with HRTEM results. In addition, the mass loss curve of TGA experiments showed that DMC addition could enhance the reactivity of soot particles.
Topics: Ethylenes; Formates; Models, Chemical; Nanostructures; Soot
PubMed: 30244737
DOI: 10.1016/j.jes.2017.12.016 -
IET Nanobiotechnology May 2019Carbon nanoparticles (CNPs) are isolated from chimney soot and characterised by various tools such as X-ray diffraction, scanning electron microscopy, transmission...
Carbon nanoparticles (CNPs) are isolated from chimney soot and characterised by various tools such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy and ultraviolet-visible spectroscopy. The X-ray diffraction studies confirm the presence of C nanoparticles in the isolated sample. The thermal properties of the prepared CNPs are recorded using thermogravimetric analysis and differential thermal analysis. The analysis of the antibacterial activity of the synthesised CNPs against selected Gram-positive and Gram-negative bacterial strains is also investigated. The systematic study confirms that CNPs collected from chimney soot exhibit good antibacterial potency against , , , and .
Topics: Anti-Bacterial Agents; Carbon; Microbial Sensitivity Tests; Microscopy, Electron; Nanoparticles; Soot; Spectrophotometry, Ultraviolet; Thermogravimetry; X-Ray Diffraction
PubMed: 31053695
DOI: 10.1049/iet-nbt.2018.5183 -
Mikrochimica Acta Feb 2020Carbon nanoparticles (NPs) from the incomplete combustion of a candle were used as matrix for surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS)....
Carbon nanoparticles (NPs) from the incomplete combustion of a candle were used as matrix for surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). The washed carbon soot NPs (WCS NPs, ~48 nm) exhibit higher laser desorption/ionization efficiency and less background compared with other common metal and carbon matrices. WCS NPs present good reproducibility and high sensitivity in analyzing a wide range of molecules in both positive and negative ionization mode in SALDI-MS. The detection limit of glucose is 1 pmol with WCS NPs as matrix. WCS NPs can be used to quantitatively determine urine glucose, visualize latent fingerprint and image it with SALDI-MS. The UV absorption of WCS NPs and MS spectra analyzed with WCS NPs matrix remain the same after 10 months storage, indicating the good stability of WCS NPs as matrix. Graphical abstractSchematic representation of carbon nanoparticles derived from carbon soot and its application as matrix in SALDI-MS.
Topics: Carbon; Nanoparticles; Soot; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 32048033
DOI: 10.1007/s00604-020-4142-x -
Chemosphere Jan 2023The purpose of the present study is to better understand the reaction kinetics of diesel exhaust soot during oxidation process. A thermogravimetric analyzer was used to...
The purpose of the present study is to better understand the reaction kinetics of diesel exhaust soot during oxidation process. A thermogravimetric analyzer was used to oxidize real diesel exhaust soot generated from a Euro VI diesel engine under non-isothermal conditions. The Friedman-Reich-Levi method and the Sestak-Berggren model were used to determine the oxidation kinetics. Raman spectroscopy and high-resolution transmission electron microscopy were employed to follow the changes of the soot structure during oxidation. The activation energy gradually increased with increasing conversion level during soot oxidation. The oxidation process of diesel exhaust soot could be described as three-step kinetics, and the calculated conversions fitted the experimental results very well. The kinetic predictions of diesel soot oxidation that were obtained using the proposed kinetic models were more accurate and precise than those with the common first-order model. The structural order increased as oxidation progressed, which was responsible for the increased activation energy. The structural ordering was principally caused by the preferential oxidation of the disordered fraction in the diesel soot, especially for the amorphous carbon, which was oxidized in the initial stage of the oxidation reaction.
Topics: Vehicle Emissions; Soot; Oxidation-Reduction; Microscopy, Electron, Transmission; Kinetics
PubMed: 36283428
DOI: 10.1016/j.chemosphere.2022.136980 -
Environmental Science. Processes &... Dec 2022Submicron soot particles (<1.0 μm in aerodynamic diameter) are responsible for global warming and health burdens worldwide. However, studies on bio-monitoring of...
Submicron soot particles (<1.0 μm in aerodynamic diameter) are responsible for global warming and health burdens worldwide. However, studies on bio-monitoring of submicron soot particles and their associated sources by using tree leaves are not comprehensively illustrated. Here, we determined the seasonal trends of submicron soot particles on the leaves of the collected from two cities (Lu'an, Anhui Province, and Nanjing, Jiangsu Province) in the Yangtze River Delta region, China. The source apportionment of submicron soot particles was performed using stable carbon isotopic analyses. Significant seasonal trends of submicron soot particles were observed in two cities with averaged levels of 0.41-1.36 mg m in cold seasons and averaged levels of 0.13-0.24 mg m in warm seasons. The levels of C for submicron soot at the suburban site of Lu'an city were observed to be in the range of -25.6‰ to -18.2‰ with fossil fuels dominated (∼58%) in summer and -23.0‰ to -15.6‰ with biomass burning dominated in winter (∼67%). In comparison, the ranges in the levels of C in submicron soot were found to be from -26.5‰ to -20.4‰ in winter, and -24.2‰ to -17.9‰ in summer at the urban site of Nanjing. Fossil fuels accounted for a large fraction of submicron soot with average contributions of 53% in winter and 73% in summer, respectively. These findings demonstrate that trees could be used as an effective and low-cost bio-monitoring tool for monitoring the pollution status of submicron soot and associated source contribution.
Topics: Soot; Trees; Air Pollutants; Environmental Monitoring; Fossil Fuels; Carbon; Seasons; China; Aerosols; Particulate Matter
PubMed: 36278318
DOI: 10.1039/d2em00328g -
Analytical Chemistry Apr 2012In this study we summarize the possibilities and limitations of a conductometric measurement principle for soot sensing. The electrical conductivity of different carbon...
In this study we summarize the possibilities and limitations of a conductometric measurement principle for soot sensing. The electrical conductivity of different carbon blacks (FW 200, lamp black 101, Printex 30, Printex U, Printex XE2, special black 4, and special black 6), spark discharge soot (GfG), and graphite powder was measured by a van der Pauw arrangement. Additionally the influence of inorganic admixtures on the conductivity of carbonaceous materials was proven to follow the percolation theory. Structural and oxidation characteristics obtained with Raman microspectroscopy and temperature programmed oxidation, respectively, were correlated with the electrical conductivity data. Moreover, a thermophoretic precipitator has been applied to deposit soot particles from the exhaust stream between interdigital electrodes. This combines a controlled and size independent particle collection method with the conductivity measurement principle. A test vehicle was equipped with the AVL Micro Soot Sensor (photoacoustic soot sensor) to prove the conductometric sensor principle with an independent and reliable technique. Our results demonstrate promising potential of the conductometric sensor for on-board particle diagnostic. Furthermore this sensor can be applied as a simple, rapid, and cheap analytical tool for characterization of soot structure.
Topics: Aerosol Propellants; Forensic Ballistics; Soot; Spectrum Analysis, Raman; Time Factors
PubMed: 22455449
DOI: 10.1021/ac203152z -
The Science of the Total Environment Jul 2012Atmospheric particles larger than 0.2 μm were collected at the top of Mt. Tai (36.25°N, 117.10°E, 1534 m a.s.l.) in eastern China in May 2008 during the passage of a...
Atmospheric particles larger than 0.2 μm were collected at the top of Mt. Tai (36.25°N, 117.10°E, 1534 m a.s.l.) in eastern China in May 2008 during the passage of a strong cyclone. The particles were analyzed with electron microscopes and characterized by morphology, equivalent diameter and elemental composition. Soot particles with coating (coated soot particles) and those without apparent coating (naked soot particles) were predominant in the diameter range smaller than 0.6 μm in all samples. The number-size distribution of the relative abundance of naked soot particles in the prefrontal air was similar to that in the postfrontal air and their size modes were around 0.2-0.3 μm. However, the distribution of inclusions of coated soot particles showed a mode in the range of 0.1-0.3 μm. The coating degree of coated soot particles, which was defined by the ratio of the diameter of inclusion to the diameter of particle body, showed a mode around 0.5 with the range of 0.3-0.6. These results indicate that the status of soot particles in the prefrontal and postfrontal air was similar although air pollution levels were dramatically different. In addition, the relative abundance of accumulation mode particles increased with the decrease of soot particles after the front passage.
Topics: Air Pollutants; China; Cyclonic Storms; Environmental Monitoring; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Particle Size; Particulate Matter; Soot; Spectrometry, X-Ray Emission
PubMed: 22652010
DOI: 10.1016/j.scitotenv.2012.04.050 -
Biointerphases Sep 2016Super nonfouling surfaces resist protein adhesion and have a broad field of possible applications in implant technology, drug delivery, blood compatible materials,...
Super nonfouling surfaces resist protein adhesion and have a broad field of possible applications in implant technology, drug delivery, blood compatible materials, biosensors, and marine coatings. A promising route toward nonfouling surfaces involves liquid repelling architectures. The authors here show that soot-templated super-amphiphobic (SAP) surfaces prepared from fluorinated candle soot structures are super nonfouling. When exposed to bovine serum albumin or blood serum, x-ray photoelectron spectroscopy and time of flight secondary ion mass spectrometry analysis showed that less than 2 ng/cm(2) of protein was adsorbed onto the SAP surfaces. Since a broad variety of substrate shapes can be coated by soot-templated SAP surfaces, those are a promising route toward biocompatible materials design.
Topics: Adsorption; Animals; Blood Proteins; Cattle; Coated Materials, Biocompatible; Humans; Photoelectron Spectroscopy; Soot; Spectrometry, Mass, Secondary Ion; Surface Properties
PubMed: 27460261
DOI: 10.1116/1.4959237