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Devoy J, Al-Abed S, Cerdan B, Cho WS, Dubuc D, Flahaut E, Grenier K, Grossmann S, Gulumian M, Jeong J, Kim BW, Laycock A, Lee JS, Smith R, Yang M, Yu IJ, Zhang M, Cosnier F. Analysis of carbon nanotube levels in organic matter: an inter-laboratory comparison to determine best practice. Nanotoxicology 2024; 18:214-228. [PMID: 38557361 DOI: 10.1080/17435390.2024.2331683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 03/11/2024] [Indexed: 04/04/2024]
Abstract
Carbon nanotubes (CNTs) are increasingly being used in industrial applications, but their toxicological data in animals and humans are still sparse. To assess the toxicological dose-response of CNTs and to evaluate their pulmonary biopersistence, their quantification in tissues, especially lungs, is crucial. There are currently no reference methods or reference materials for low levels of CNTs in organic matter. Among existing analytical methods, few have been fully and properly validated. To remedy this, we undertook an inter-laboratory comparison on samples of freeze-dried pig lung, ground and doped with CNTs. Eight laboratories were enrolled to analyze 3 types of CNTs at 2 concentration levels each in this organic matrix. Associated with the different analysis techniques used (specific to each laboratory), sample preparation may or may not have involved prior digestion of the matrix, depending on the analysis technique and the material being analyzed. Overall, even challenging, laboratories' ability to quantify CNT levels in organic matter is demonstrated. However, CNT quantification is often overestimated. Trueness analysis identified effective methods, but systematic errors persisted for some. Choosing the assigned value proved complex. Indirect analysis methods, despite added steps, outperform direct methods. The study emphasizes the need for reference materials, enhanced precision, and organized comparisons.
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Affiliation(s)
- Jérôme Devoy
- Institut National de Recherche et de Sécurité (INRS), Vandœuvre-lès-Nancy, CS, France
| | - Souhail Al-Abed
- Center for Environmental Solutions and Emergency Response, U.S. Environmental Protection Agency, Cincinnati, OH, USA
| | - Benjamin Cerdan
- LAAS-CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France
- CIRIMAT, Université Toulouse 3 Paul Sabatier, Toulouse INP, CNRS, Université de Toulouse, Toulouse, France
| | - Wan-Seob Cho
- Laboratory of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, Busan, South Korea
| | - David Dubuc
- LAAS-CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Emmanuel Flahaut
- CIRIMAT, Université Toulouse 3 Paul Sabatier, Toulouse INP, CNRS, Université de Toulouse, Toulouse, France
| | - Katia Grenier
- LAAS-CNRS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Stéphane Grossmann
- Institut National de Recherche et de Sécurité (INRS), Vandœuvre-lès-Nancy, CS, France
| | - Mary Gulumian
- National Institute for Occupational Health (NIOH), Johannesburg, South Africa
| | - Jiyoung Jeong
- Laboratory of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, Busan, South Korea
| | - Boo Wook Kim
- Korea Worker's Compensation & Welfare Service, Occupational Environment Research Institute, Icheon, Gyeonggi-do, South Korea
| | - Adam Laycock
- UK Health Security Agency, Radiation, Chemicals and Environmental Hazards, Harwell Science Campus, Didcot, Oxfordshire, UK
| | - Jong Seong Lee
- Aerosol Toxicology Research Center, HCTM, Icheon, Gyeonggi-do, South Korea
| | - Rachel Smith
- UK Health Security Agency, Radiation, Chemicals and Environmental Hazards, Harwell Science Campus, Didcot, Oxfordshire, UK
| | - Mei Yang
- Nano Carbon Device Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
| | - Il Je Yu
- Aerosol Toxicology Research Center, HCTM, Icheon, Gyeonggi-do, South Korea
| | - Minfang Zhang
- Nano Carbon Device Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
| | - Frédéric Cosnier
- Institut National de Recherche et de Sécurité (INRS), Vandœuvre-lès-Nancy, CS, France
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Park SH, Kim G, Yang GE, Yun HJ, Shin TH, Kim ST, Lee K, Kim HS, Kim SH, Leem SH, Cho WS, Lee JH. Disruption of phosphofructokinase activity and aerobic glycolysis in human bronchial epithelial cells by atmospheric ultrafine particulate matter. JOURNAL OF HAZARDOUS MATERIALS 2024; 464:132966. [PMID: 37976851 DOI: 10.1016/j.jhazmat.2023.132966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/28/2023] [Accepted: 11/07/2023] [Indexed: 11/19/2023]
Abstract
Exposure to ambient ultrafine particulate matter (UPM) causes respiratory disorders; however, the underlying molecular mechanisms remain unclear. In this study, we synthesized simulated UPM (sUPM) with controlled physicochemical properties using the spark-discharge method. Subsequently, we investigated the biological effects of sUPM using BEAS-2B human bronchial epithelial cells (HBECs) and a mouse intratracheal instillation model. High throughput RNA-sequencing and bioinformatics analyses revealed that dysregulation of the glycolytic metabolism is involved in the inhibited proliferation and survival of HBECs by sUPM treatment. Furthermore, signaling pathway and enzymatic analyses showed that the treatment of BEAS-2B cells with sUPM induces the inactivation of extracellular signal-regulated kinase (ERK) and protein kinase B (PKB, also known as AKT), resulting in the downregulation of phosphofructokinase 2 (PFK2) S483 phosphorylation, PFK enzyme activity, and aerobic glycolysis in HBECs in an oxidative stress-independent manner. Additionally, intratracheal instillation of sUPM reduced the phosphorylation of ERK, AKT, and PFK2, decreased proliferation, and increased the apoptosis of bronchial epithelial cells in mice. The findings of this study imply that UPM induces pulmonary toxicity by disrupting aerobic glycolytic metabolism in lung epithelial cells, which can provide novel insights into the toxicity mechanisms of UPM and strategies to prevent their toxic effects.
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Affiliation(s)
- Su Hwan Park
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea
| | - Gyuri Kim
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea
| | - Gi-Eun Yang
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea
| | - Hye Jin Yun
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea
| | - Tae Hwan Shin
- Department of Biomedical Sciences, Dong-A University, Busan 49315, Republic of Korea
| | - Sun Tae Kim
- Department of Plant Bioscience, Life and Industry Convergence Research Institute, Pusan National University, Miryang 50463, Republic of Korea
| | - Kyuhong Lee
- Inhalation Toxicology Center for Airborne Risk Factor, Korea Institute of Toxicology, 30 Baehak1-gil, Jeongeup, Jeollabuk-do, 56212, Republic of Korea
| | - Hyuk Soon Kim
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea; Department of Biomedical Sciences, Dong-A University, Busan 49315, Republic of Korea
| | - Seok-Ho Kim
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea
| | - Sun-Hee Leem
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea; Department of Biomedical Sciences, Dong-A University, Busan 49315, Republic of Korea.
| | - Wan-Seob Cho
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea.
| | - Jong-Ho Lee
- Department of Health Sciences, The Graduate School of Dong-A University, Busan 49315, Republic of Korea; Department of Biomedical Sciences, Dong-A University, Busan 49315, Republic of Korea.
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Jeong J, Jeon S, Kim S, Lee S, Kim G, Bae E, Ha Y, Lee SW, Kim JS, Kim DJ, Cho WS. Effect of sp 3/sp 2 carbon ratio and hydrodynamic size on the biodistribution kinetics of nanodiamonds in mice via intravenous injection. Part Fibre Toxicol 2023; 20:33. [PMID: 37605240 PMCID: PMC10440929 DOI: 10.1186/s12989-023-00545-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 08/17/2023] [Indexed: 08/23/2023] Open
Abstract
BACKGROUND Nanodiamonds (NDs) have gained a rapidly growing interest in biomedical applications; however, little is known regarding their biokinetics owing to difficulties in measurements and limited synthesis/purification technologies. In this study, we investigated the distribution kinetics of detonation-synthesized NDs in mice via intravenous injection to evaluate the parameters that determine the behavior of the particles. We prepared two distinctive NDs that controlled the sp3/sp2 carbon ratio and particle size by coating them with serum proteins. The four control samples were intravenously injected into mice, and tissue distribution and clearance were evaluated at 30 min and 1, 7, and 28 days post-injection. RESULTS The sp3/sp2 carbon ratio showed no correlation with the organ distribution of the NDs. However, hydrodynamic size showed an excellent correlation with organ distribution levels: a negative correlation in the liver and positive correlations in the spleen and lungs. Furthermore, the deposition levels of NDs in the lung suggest that particles smaller than 300 nm could avoid lung deposition. Finally, a similar organ distribution pattern was observed in mice injected with carbon black nanoparticles controlled hydrodynamic size. CONCLUSIONS In conclusion, the tissue distribution of NDs is modulated not by the sp3/sp2 carbon ratio but by the hydrodynamic size, which can provide helpful information for targeting the tissue of NDs. Furthermore, the organ distribution pattern of the NDs may not be specific to NDs but also can apply to other nanoparticles, such as carbon black.
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Affiliation(s)
- Jiyoung Jeong
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Soyeon Jeon
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Songyeon Kim
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Sinuk Lee
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Gyuri Kim
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Eunsol Bae
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Yeonjeong Ha
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea
| | - Seung Whan Lee
- Plasma Technology Research Center, National Fusion Research Institute, Gunsan-si, 54004, Republic of Korea
| | - Ji-Su Kim
- Primate Resources Center (PRC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Jeongeup, 56216, Republic of Korea
| | - Dong-Jae Kim
- Laboratory Animal Resource Center, DGIST, Daegu, 42988, Republic of Korea
| | - Wan-Seob Cho
- Lab of Toxicology, Department of Health Sciences, Dong-A University, Busan, 49315, Republic of Korea.
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Jeon S, Lee WS, Song KS, Jeong J, Lee S, Kim S, Kim G, Kim JS, Jeong J, Cho WS. Differential particle and ion kinetics of silver nanoparticles in the lungs and biotransformation to insoluble silver sulfide. JOURNAL OF HAZARDOUS MATERIALS 2023; 452:131223. [PMID: 36948120 DOI: 10.1016/j.jhazmat.2023.131223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 02/23/2023] [Accepted: 03/14/2023] [Indexed: 05/03/2023]
Abstract
The measurement of nanoparticles (NPs) in a biological matrix is essential in various toxicity studies. However, the current knowledge has limitations in differentiating particulate and ionic forms and further identification of their biotransformation. Herein, we evaluate the biotransformation and differential lung clearance kinetics of particulate and ionic forms using PEGylated silver NPs (AgNP-PEGs; 47.51 nm) and PEGylated gold NPs (AuNP-PEGs; 11.76 nm). At 0, 3, and 6 h and 1, 3, 7, and 14 days after a single pharyngeal aspiration in mice at 25 μg/mouse, half of the lung is digested by proteinase K (PK) to separate particulates and ions, and the other half is subjected to the acid digestion method for comparison. The quantitative and qualitative evaluation of lung clearance kinetics suggests that AgNP-PEGs are quickly dissolved and transformed into insoluble silver sulfide (Ag2S), which shows a fast-clearing early phase (0 -6 h; particle T1/2: 4.8 h) and slow-clearing late phase (1 -14 days; particle T1/2: 13.20 days). In contrast, AuNP-PEGs were scarcely cleared or biotransformed in the lungs for 14 days. The lung clearance kinetics of AgNPs and biotransformation shown in this study can be informed by the PK digestion method and cannot be obtained using the acid digestion method.
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Affiliation(s)
- Soyeon Jeon
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-daero 550 beon-gil, Saha-gu, Busan 49315, the Republic of Korea
| | - Wang Sik Lee
- Environmental Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, the Republic of Korea
| | - Kyung Seuk Song
- Korea Conformity Laboratories, 8, Gaetbeol-ro 145 beon-gil, Yeonsu-gu, Incheon 21999, the Republic of Korea
| | - Jiyoung Jeong
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-daero 550 beon-gil, Saha-gu, Busan 49315, the Republic of Korea
| | - Sinuk Lee
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-daero 550 beon-gil, Saha-gu, Busan 49315, the Republic of Korea
| | - Songyeon Kim
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-daero 550 beon-gil, Saha-gu, Busan 49315, the Republic of Korea
| | - Gyuri Kim
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-daero 550 beon-gil, Saha-gu, Busan 49315, the Republic of Korea
| | - Ji-Su Kim
- Primate Resources Center (PRC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Jeongeup 56216, the Republic of Korea
| | - Jinyoung Jeong
- Environmental Disease Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, the Republic of Korea; KRIBB School, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, the Republic of Korea.
| | - Wan-Seob Cho
- Lab of Toxicology, Department of Health Sciences, The Graduate School of Dong-A University, 37, Nakdong-daero 550 beon-gil, Saha-gu, Busan 49315, the Republic of Korea.
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Balkrishna A, Tomar M, Bhattacharya K, Varshney A. Withania somnifera-derived carbon dots protect human epidermal cells against UVB-induced cell death and support growth factor-mediated wound healing. NANOSCALE ADVANCES 2023; 5:1331-1344. [PMID: 36866265 PMCID: PMC9972854 DOI: 10.1039/d2na00545j] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/27/2022] [Indexed: 06/18/2023]
Abstract
Solar radiation comprising UVA and UVB regions is considered a skin-damaging factor inducing inflammation, oxidative stress, hyperpigmentation, and photo-aging. Photoluminescent carbon dots (CDs) were synthesized from the root extract of a Withania somnifera (L.) Dunal plant and urea, using a one-step microwave method. These Withania somnifera CDs (wsCDs) were 14.4 ± 0.18 d nm in diameter and presented photoluminescence. UV absorbance showed the presence of π-π* (C[double bond, length as m-dash]C) and n-π* (C[double bond, length as m-dash]O) transition regions in wsCDs. FTIR analysis indicated the presence of nitrogen and carboxylic functional groups on the surface of wsCDs. HPLC analysis of wsCDs showed the presence of withanoside IV, withanoside V, and withanolide A. The wsCDs were found to be biocompatible in human skin epidermal (A431) cells and hindered UVB irradiation-induced loss of metabolic activity and oxidative stress. The wsCDs supported rapid dermal wound healing through augmented TGF-β1 and EGF gene expression levels in A431 cells. Finally, wsCDs were found to be biodegradable through a myeloperoxidase-catalyzed peroxidation reaction. The study concluded that under in vitro conditions, Withania somnifera root extract-derived biocompatible carbon dots provided photo-protection against UVB-stimulated epidermal cell damage and supported rapid wound healing.
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Affiliation(s)
- Acharya Balkrishna
- Drug Discovery and Development Division, Patanjali Research Institute Haridwar India
- Department of Allied and Applied Sciences, University of Patanjali Haridwar India
- Patanjali Yog Peeth (UK) Trust 40 Lambhill Street, Kinning Park UK
| | - Meenu Tomar
- Drug Discovery and Development Division, Patanjali Research Institute Haridwar India
| | - Kunal Bhattacharya
- Drug Discovery and Development Division, Patanjali Research Institute Haridwar India
| | - Anurag Varshney
- Drug Discovery and Development Division, Patanjali Research Institute Haridwar India
- Department of Allied and Applied Sciences, University of Patanjali Haridwar India
- Special Centre for Systems Medicine, Jawahar Lal Nehru University New Delhi India
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Gao Y, Zhang R, Sun H, Guo Y, Chen L, Shi X, Ge G. High-efficiency mechanically assisted alkaline extraction of nanoparticles from biological tissues for spICP-MS analysis. Anal Bioanal Chem 2022; 414:4401-4408. [PMID: 35175388 DOI: 10.1007/s00216-022-03972-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 11/21/2022]
Abstract
The widespread use and increased exposure of nanoparticles call for technology to quantify their concentration and size distribution in biological matrices. As ex situ evaluation, facile extraction with high fidelity and efficiency is critical. In this work, single particle inductively coupled plasma mass spectrometry (spICP-MS) was used for nanoparticle number and distribution analysis, where a facile and highly efficient mechanically assisted alkaline digestion has been developed to extract nanoparticles at low alkali concentration. The optimization was performed using chicken tissues in vitro mixed with 30 nm gold nanoparticles, mixture of 30 nm and 60 nm gold nanoparticles, and 45 nm silver nanoparticles, respectively, which is, then, mechanically ground to form tissue homogenate and 2% TMAH is added. The nanoparticles are extracted with a recovery of more than 94% for all the spiked nanoparticle tissue samples. The extraction method has also been attempted to be applied to extract single-sized gold nanoparticles from various organs of mice mixed in vivo with the nanoparticles through intravenous injection, and led to consistent results with acid digestion. Mice injected intravenously with double-sized gold nanoparticle mixture were also studied, further showing that gold nanoparticles of 30 nm and 60 nm have no significant difference in their biodistribution in the same organ. To the best of our knowledge, this is the first attempt for multiple nanoparticles being extracted simultaneously and measured quantitatively from various organs, such as the heart, liver, spleen, lungs, and kidneys. We believe this method is beneficial to the safety assessment and toxicokinetics studies for nanoparticles in tissues.
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Affiliation(s)
- Ya Gao
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China.,CAS Key Laboratory of Standardization and Measurement for Nanotechnology, Beijing, 100190, People's Republic of China.,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Ruiyi Zhang
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China.,CAS Key Laboratory of Standardization and Measurement for Nanotechnology, Beijing, 100190, People's Republic of China.,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Huizhen Sun
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China.,Beijing University of Chinese Medicine, Beijing, 100102, People's Republic of China
| | - Yuting Guo
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China. .,CAS Key Laboratory of Standardization and Measurement for Nanotechnology, Beijing, 100190, People's Republic of China.
| | - Lan Chen
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China. .,CAS Key Laboratory of Standardization and Measurement for Nanotechnology, Beijing, 100190, People's Republic of China.
| | - Xiaoli Shi
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China
| | - Guanglu Ge
- CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, People's Republic of China. .,CAS Key Laboratory of Standardization and Measurement for Nanotechnology, Beijing, 100190, People's Republic of China.
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Sanjuan-Navarro L, Moliner-Martínez Y, Campíns-Falcó P. Characterization and Quantitation of Carbon Black Nanomaterials in Polymeric and Biological Aqueous Dispersants by Asymmetrical Flow Field Flow Fractionation. ACS OMEGA 2021; 6:31822-31830. [PMID: 34870005 PMCID: PMC8637946 DOI: 10.1021/acsomega.1c04527] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 11/02/2021] [Indexed: 06/13/2023]
Abstract
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.
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