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Liu J, Zhao J, Louie SM, Gao X, Zhang P, Liang D, Hu Y. Comparative study on effects of pH, electrolytes, and humic acid on the stability of acetic and polyacrylic acid coated magnetite nanoparticles. CHEMOSPHERE 2023; 319:137992. [PMID: 36720411 DOI: 10.1016/j.chemosphere.2023.137992] [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: 10/29/2022] [Revised: 01/17/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
The poor colloidal stability of magnetite nanoparticles (MNPs) limits their mobility and application, so various organic coatings (OCs) were applied to MNPs. Here, a comparative study on the colloidal stability of MNPs coated with acetic (HAc) and polyacrylic acids (PAA) was conducted under varied pH (5.0-9.0) in the presence of different concentrations of cations and anions, as well as humic acid (HA). Comparing the effects of various cations and anions, the stability of both HAc/PAA-MNPs followed the order: Na+ > Ca2+and PO43- > SO42- > Cl-, which could be explained by their adsorption behaviors onto HAc/PAA-MNPs and the resulting surface charge changes. Under all conditions even with more anion adsorption onto HAc-MNPs (0.14-22.56 mg/g) than onto PAA-MNPs (0.04-18.34 mg/g), PAA-MNPs were more negatively charged than HAc-MNPs, as PAA has a lower pHIEP (2.6 ± 0.1) than that of HAc (3.7 ± 0.1). Neither the HAc nor PAA coatings were displaced by phosphate even at considerably high phosphate concentration. Compared with HAc-MNPs, the stability of PAA-MNPs was greatly improved under all studied conditions, which could be due to both stronger electrostatic and additional steric repulsion forces among PAA-MNPs. Besides, under all conditions, Derjaguin-Landau-Verwey-Overbeek (DLVO) explained well the aggregation kinetic of HAc-MNPs; while extended DLVO (EDLVO) successfully predict that of PAA-MNPs, indicating steric forces among PAA-MNPs. The aggregation of HAc/PAA-MNPs was all inhibited in varied electrolyte solutions by HA (2 mg C/L) addition. This study suggested that carboxyl coatings with higher molecular weights and pKa values could stabilize MNPs better due to stronger electrostatic and additional steric repulsion. However, in the presence of HA, these two forces were mainly controlled by adsorbed HA instead of the organic pre-coatings on MNPs.
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Affiliation(s)
- Juanjuan Liu
- State Key Laboratory of Biogeology & Environmental Geology and School of Environmental Studies, China University of Geosciences, Wuhan, Hubei, 430074, PR China; College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China; The Key Laboratory of Water and Sediment Sciences (Ministry of Education), State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Juntao Zhao
- Department of Civil & Environmental Engineering, University of Houston, Houston, TX, 77004, United States; Benchmark Lab & Services, Houston, TX, 77092, United States
| | - Stacey M Louie
- Department of Civil & Environmental Engineering, University of Houston, Houston, TX, 77004, United States
| | - Xubo Gao
- State Key Laboratory of Biogeology & Environmental Geology and School of Environmental Studies, China University of Geosciences, Wuhan, Hubei, 430074, PR China
| | - Ping Zhang
- Faculty of Science and Technology, University of Macau, Macau, 999078, China
| | - Dongli Liang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China.
| | - Yandi Hu
- The Key Laboratory of Water and Sediment Sciences (Ministry of Education), State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China.
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Philip J. Magnetic nanofluids (Ferrofluids): Recent advances, applications, challenges, and future directions. Adv Colloid Interface Sci 2023; 311:102810. [PMID: 36417827 DOI: 10.1016/j.cis.2022.102810] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/28/2022] [Accepted: 11/05/2022] [Indexed: 11/16/2022]
Abstract
Impelled by the need to find solutions to new challenges of modern technologies new materials with unique properties are being explored. Among various new materials that emerged over the decades, magnetic fluids exhibiting interesting physiochemical properties (optical, thermal, magnetic, rheological, apparent density, etc.) under a magnetic stimulus have been at the forefront of research. In the initial phase, there has been a fervent scientific curiosity to understand the field-induced intriguing properties of such fluids but later a plethora of technological applications emerged. Magnetic nanofluid, popularly known as ferrofluid, is a colloidal suspension of fine magnetic nanoparticles, has been at the forefront of research because of its magnetically tunable physicochemical properties and applications. Due to their stimuli-responsive behaviour, they have been finding more applications in biology and other engineering disciplines in recent years. Therefore, a critical review of this topic highlighting the necessary background, the potential of this material for emerging technologies, and the latest developments is warranted. This review also provides a summary of various applications, along with the key challenges and future research directions. The first part of the review addresses the different types of magnetic fluids, the genesis of magnetic fluids, their synthesis methodologies, properties, and stabilization techniques are discussed in detail. The second part of the review highlights the applications of magnetic nanofluids and nanoemulsions (as model systems) in probing order-disorder transitions, scattering, diffraction, magnetically reconfigurable internal structures, molecular interaction, and weak forces between colloidal particles, conformational changes of macromolecules at interfaces and polymer-surfactant complexation at the oil-water interface. The last part of the review summarizes the interesting applications of magnetic fluids such as heat transfer, sensors (temperature, pH, urea detection, cations, defect detection sensors), tunable optical filters, removal of dyes, dynamic seals, magnetic hyperthermia-based cancer therapy and other biomedical applications. The applications of magnetic nanofluids in diverse disciplines are growing day by day, yet there are challenges in their practical adaptation as field-worthy or packaged products. This review provides a pedagogical description of magnetic fluids, with the necessary background, key concepts, physics, experimental protocols, design of experiments, challenges and future directions.
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Affiliation(s)
- John Philip
- Smart Materials Section, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, India.
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Stable Magnetorheological Fluids Containing Bidisperse Fillers with Compact/Mesoporous Silica Coatings. Int J Mol Sci 2022; 23:ijms231911044. [PMID: 36232347 PMCID: PMC9570470 DOI: 10.3390/ijms231911044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/08/2022] [Accepted: 09/17/2022] [Indexed: 11/16/2022] Open
Abstract
A drawback of magnetorheological fluids is low kinetic stability, which severely limits their practical utilization. This paper describes the suppression of sedimentation through a combination of bidispersal and coating techniques. A magnetic, sub-micro additive was fabricated and sequentially coated with organosilanes. The first layer was represented by compact silica, while the outer layer consisted of mesoporous silica, obtained with the oil–water biphase stratification method. The success of the modification technique was evidenced with transmission electron microscopy, scanning electron microscopy/energy-dispersive X-ray spectroscopy and Fourier-transform infrared spectroscopy. The coating exceptionally increased the specific surface area, from 47 m2/g (neat particles) up to 312 m2/g, which when combined with lower density, resulted in remarkable improvement in the sedimentation profile. At this expense, the compact/mesoporous silica slightly diminished the magnetization of the particles, while the magnetorheological performance remained at an acceptable level, as evaluated with a modified version of the Cross model. Sedimentation curves were, for the first time in magnetorheology, modelled via a novel five-parameter equation (S-model) that showed a robust fitting capability. The sub-micro additive prevented the primary carbonyl iron particles from aggregation, which was projected into the improved sedimentation behavior (up to a six-fold reduction in the sedimentation rate). Detailed focus was also given to analyze the implications of the sub-micro additives and their surface texture on the overall behavior of the bidisperse magnetorheological fluids.
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Liu J, Louie SM, Zhao J, Gao X, Hu Y. Aggregation of varied organic coated magnetite nanoparticles: Adsorbed mass and thickness of coatings and interactions with natural organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 831:154976. [PMID: 35378183 DOI: 10.1016/j.scitotenv.2022.154976] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
Magnetite nanoparticles (MNPs) with varied organic coatings (OCs) which improved their stability have broad environmental applications. However, the adsorbed amounts and layer thickness of varied OCs onto MNPs during the synthesis were generally not or poorly characterized, and their interactions with natural organic matter (NOM) were still in progress. In this study, acetic (HAc), citric (CA), and polyacrylic acid (PAA) were selected as model OCs, the adsorption behaviors of OCs on MNPs were characterized under varied aqueous C/Fe ratios, and the aggregation behaviors of MNPs with varied OCs (OC-MNPs) at neutral pH (7.0 ± 0.2) with NaCl (5-800 mM) in the presence/absence of NOM were systematically investigated. Under low aqueous C/Fe ratio, the adsorbed amounts of model OCs as -COOH/Fe ratio followed the order: CA ≈ PAA > > HAc. With high aqueous C/Fe ratio, the maximum adsorbed masses of OC-MNPs were similar. The adsorbed layer thicknesses of OC-MNPs were thoroughly characterized using three different methods, all showing that the adsorbed layer of PAA was thicker than that of CA and HAc. Derjaguin-Landau-Verwey-Overbeek (DLVO) and extended DLVO (EDLVO) calculations showed that electrostatic and van der Waals forces were dominant for CA-MNPs and HAc-MNPs stabilization; while steric repulsion played major roles in stabilizing PAA-MNPs, probably due to a thicker PAA layer. In the presence of NOM, stability behaviors of all OC-MNPs were similar, ascribing to the much greater amounts of NOM adsorbed than the OCs, causing greater steric repulsion. This study provides new mechanistic insights which could help better understand the effects of varied OCs on MNPs' colloidal stability.
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Affiliation(s)
- Juanjuan Liu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; State Key Laboratory of Biogeology & Environmental Geology, School of Environmental Studies, China University of Geosciences, Wuhan, Hubei 430074, China
| | - Stacey M Louie
- Department of Civil & Environmental Engineering, University of Houston, Houston, TX 77004, United States
| | - Juntao Zhao
- Department of Civil & Environmental Engineering, University of Houston, Houston, TX 77004, United States; Benchmark Lab & Services, Houston, TX 77092, United States
| | - Xubo Gao
- State Key Laboratory of Biogeology & Environmental Geology, School of Environmental Studies, China University of Geosciences, Wuhan, Hubei 430074, China
| | - Yandi Hu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
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Nanohybrid Membrane Synthesis with Phosphorene Nanoparticles: A Study of the Addition, Stability and Toxicity. Polymers (Basel) 2020; 12:polym12071555. [PMID: 32674304 PMCID: PMC7408299 DOI: 10.3390/polym12071555] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 01/08/2023] Open
Abstract
Phosphorene is a promising candidate as a membrane material additive because of its inherent photocatalytic properties and electrical conductance which can help reduce fouling and improve membrane properties. The main objective of this study was to characterize structural and morphologic changes arising from the addition of phosphorene to polymeric membranes. Here, phosphorene was physically incorporated into a blend of polysulfone (PSf) and sulfonated poly ether ether ketone (SPEEK) doping solution. Protein and dye rejection studies were carried out to determine the permeability and selectivity of the membranes. Since loss of material additives during filtration processes is a challenge, the stability of phosphorene nanoparticles in different environments was also examined. Furthermore, given that phosphorene is a new material, toxicity studies with a model nematode, Caenorhabditis elegans, were carried out to provide insight into the biocompatibility and safety of phosphorene. Results showed that membranes modified with phosphorene displayed a higher protein rejection, but lower flux values. Phosphorene also led to a 70% reduction in dye fouling after filtration. Additionally, data showed that phosphorene loss was negligible within the membrane matrix irrespective of the pH environment. Phosphorene caused toxicity to nematodes in a free form, while no toxicity was observed for membrane permeates.
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Ma L, Bao L, Hu D, Zhao L, Liu T. Effect of interfacial properties on the stability of ultra-dry CO2-in-water (C/W) foams stabilized with zwitterionic surfactants and nonionic/anionic polymers: Experimental and DPD simulation. J Supercrit Fluids 2020. [DOI: 10.1016/j.supflu.2019.104722] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Wang Y, Xie W, Wu D. Rheological properties of magnetorheological suspensions stabilized with nanocelluloses. Carbohydr Polym 2020; 231:115776. [DOI: 10.1016/j.carbpol.2019.115776] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/12/2019] [Accepted: 12/20/2019] [Indexed: 12/24/2022]
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8
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Mintis DG, Mavrantzas VG. Effect of pH and Molecular Length on the Structure and Dynamics of Short Poly(acrylic acid) in Dilute Solution: Detailed Molecular Dynamics Study. J Phys Chem B 2019; 123:4204-4219. [DOI: 10.1021/acs.jpcb.9b01696] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dimitris G. Mintis
- Department of Chemical Engineering, University of Patras & FORTH-ICE/HT, Patras GR26504, Greece
| | - Vlasis G. Mavrantzas
- Department of Chemical Engineering, University of Patras & FORTH-ICE/HT, Patras GR26504, Greece
- Particle Technology Laboratory, Department of Mechanical and Process Engineering, ETH Zürich, CH-8092 Zürich, Switzerland
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Li Q, Prigiobbe V. Modeling Nanoparticle Transport in Porous Media in the Presence of a Foam. Transp Porous Media 2019. [DOI: 10.1007/s11242-019-01235-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Silakul P, Magaraphan R. Polymer Electrolyte from Natural Rubber-Polyacrylic Acid and Polypyrrole and Its Application. Macromol Res 2019. [DOI: 10.1007/s13233-019-7023-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Liu Y, Yang T, Wang L, Huang Z, Li J, Cheng H, Jiang J, Pang S, Qi J, Ma J. Interpreting the effects of natural organic matter on antimicrobial activity of Ag 2S nanoparticles with soft particle theory. WATER RESEARCH 2018; 145:12-20. [PMID: 30118974 DOI: 10.1016/j.watres.2018.07.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/23/2018] [Accepted: 07/25/2018] [Indexed: 06/08/2023]
Abstract
Natural organic matter (NOM) ubiquitously exists in natural waters and would adsorb onto the particle surface. Previous studies showed that NOM would alleviate the toxicity of nanomaterials, while the mechanism is seldom quantitatively interpreted. Herein, the effects of humic substances [Suwannee River fulvic acid (SRFA) and Suwannee River humic acid (SRHA)] and biomacromolecules [alginate and bovine serum albumin (BSA)] on the aggregation and antimicrobial effects of silver sulfide nanoparticles (Ag2S-NPs) were investigated. The aggregation kinetics of Ag2S-NPs in electrolyte solutions were in agreement with the results based on Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The dynamic light scattering (DLS) results showed that the SRFA, SRHA, alginate and BSA molecules coated on the Ag2S-NPs surfaces. The NOM coating layer prevented salt-induced coagulation of Ag2S-NPs, and the effects of BSA and SRHA on Ag2S-NPs stabilizing were more obvious than that of SRFA and alginate. Flow cytometry analysis results suggested that BSA and SRHA were more effective on alleviating the Ag2S-NPs induced cell (Escherichia coli) membrane damage than SRFA and alginate. After interpreting the electrophoretic mobility (EPM) data of the NOM coated Ag2S-NPs by Ohshima's soft particle theory, it was found that the thickness of the NOM coating layers followed the orders of BSA > SRHA > alginate > SRFA. The E.coli cell membrane damage level was negatively correlated with the thickness and softness of the coating layer. NOM coating may physically alleviate the contact between NPs and E. coli cells and thus attenuate the extent of cell membrane damage caused by the NP-cell interaction. This work provides a new perspective for quantitatively interpreting the influence of NOM on the environmental behaviors and risks of nanomaterials.
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Affiliation(s)
- Yulei Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Tao Yang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Lu Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Zhuangsong Huang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Juan Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Haijun Cheng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jin Jiang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Suyan Pang
- School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun, 130118, China
| | - Jingyao Qi
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
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Xu J, Li J, Cao J. Effects of fumed silica weight fraction on rheological properties of magnetorheological polishing fluids. Colloid Polym Sci 2018. [DOI: 10.1007/s00396-018-4332-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Kim MW, Bae DH, Kwon SH, Choi HJ. Magnetite Embedded Mini-Emulsion Polymerized Polystyrene Particles and Their Magnetorheology. Macromol Res 2018. [DOI: 10.1007/s13233-018-6048-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Gao CY, Kim MW, Bae DH, Dong YZ, Piao SH, Choi HJ. Fe3O4 nanoparticle-embedded polystyrene composite particles fabricated via a Shirasu porous glass membrane technique and their magnetorheology. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.07.079] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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15
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Liu Q, Li H, Lam KY. Development of a Multiphysics Model to Characterize the Responsive Behavior of Magnetic-Sensitive Hydrogels with Finite Deformation. J Phys Chem B 2017; 121:5633-5646. [DOI: 10.1021/acs.jpcb.7b01089] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Qimin Liu
- School of Mechanical and
Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Republic of Singapore
| | - Hua Li
- School of Mechanical and
Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Republic of Singapore
| | - K. Y. Lam
- School of Mechanical and
Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Republic of Singapore
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Kosmulski M. Isoelectric points and points of zero charge of metal (hydr)oxides: 50years after Parks' review. Adv Colloid Interface Sci 2016; 238:1-61. [PMID: 27890403 DOI: 10.1016/j.cis.2016.10.005] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 10/27/2016] [Accepted: 10/28/2016] [Indexed: 02/06/2023]
Abstract
The pH-dependent surface charging of metal (hydr)oxides is reviewed on the occasion of the 50th anniversary of the publication by G.A. Parks: "Isoelectric points of solid oxides, solid hydroxides, and aqueous hydroxo complex systems" in Chemical Reviews. The point of zero charge (PZC) and isoelectric point (IEP) became standard parameters to characterize metal oxides in aqueous dispersions, and they define adsorption (surface excess) of ions, stability against coagulation, rheological properties of dispersions, etc. They are commonly used in many branches of science including mineral processing, soil science, materials science, geochemistry, environmental engineering, and corrosion science. Parks established standard procedures and experimental conditions which are required to obtain reliable and reproducible values of PZC and IEP. The field is very active, and the number of related papers exceeds 300 a year, and the standards established by Parks remain still valid. Relevant experimental techniques improved over the years, especially the measurements of electrophoretic mobility became easier and more reliable, are the numerical values of PZC and IEP compiled by Parks were confirmed by contemporary publications with a few exceptions. The present paper is an up-to-date compilation of the values of PZC and IEP of metal oxides. Unlike in former reviews by the same author, which were more comprehensive, only limited number of selected results are presented and discussed here. On top of the results obtained by means of classical methods (titration and electrokinetic methods), new methods and correlations found over the recent 50years are presented.
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Moon IJ, Kim MW, Choi HJ, Kim N, You CY. Fabrication of dopamine grafted polyaniline/carbonyl iron core-shell typed microspheres and their magnetorheology. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2016.04.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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18
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Lee S, Shin KY, Jang J. Enhanced magnetorheological performance of highly uniform magnetic carbon nanoparticles. NANOSCALE 2015; 7:9646-9654. [PMID: 25959283 DOI: 10.1039/c4nr07168a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Magnetic carbon nanoparticles (MC NPs) are prepared on a multi-gram scale through carbonization of iron-doped polypyrrole nanoparticles (PPy NPs). Three different-sized MC NPs (ca. 40, 60 and 90 nm) are prepared and adopted as dispersing materials for magnetorheological (MR) fluids to investigate the influence of particle size on MR properties. The MC NP-based MR fluids exhibit outstanding MR performances compared to the conventional magnetic carbon material-based fluids. In addition, the MR activities are enhanced with decreasing particle diameter and increasing applied magnetic field strength. Furthermore, anti-sedimentation properties are examined in order to achieve in-depth insight into the effect of the particle size on MR fluids.
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Affiliation(s)
- Seungae Lee
- School of Chemical and Biological Engineering, College of Engineering, Seoul National University (SNU), Seoul, Korea.
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McDaniel K, Valcius F, Andrews J, Das S. Electrostatic potential distribution of a soft spherical particle with a charged core and pH-dependent charge density. Colloids Surf B Biointerfaces 2015; 127:143-7. [DOI: 10.1016/j.colsurfb.2015.01.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 01/11/2015] [Accepted: 01/14/2015] [Indexed: 10/24/2022]
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20
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Machovský M, Mrlík M, Plachý T, Kuřitka I, Pavlínek V, Kožáková Z, Kitano T. The enhanced magnetorheological performance of carbonyl iron suspensions using magnetic Fe3O4/ZHS hybrid composite sheets. RSC Adv 2015. [DOI: 10.1039/c4ra14054k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The facile two-step microwave-assisted synthesis of Fe3O4/ZHS hybrid composite sheets with 2D morphology considerably improves the MR performance and suspension redispersibility.
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Affiliation(s)
- Michal Machovský
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
| | - Miroslav Mrlík
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
| | - Tomáš Plachý
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
| | - Ivo Kuřitka
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
| | - Vladimír Pavlínek
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
| | - Zuzana Kožáková
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
| | - Takeshi Kitano
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- 760 01 Zlin
- Czech Republic
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Singh D, McMillan JM, Liu XM, Vishwasrao HM, Kabanov AV, Sokolsky-Papkov M, Gendelman HE. Formulation design facilitates magnetic nanoparticle delivery to diseased cells and tissues. Nanomedicine (Lond) 2014; 9:469-85. [PMID: 24646020 DOI: 10.2217/nnm.14.4] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Magnetic nanoparticles (MNPs) accumulate at disease sites with the aid of magnetic fields; biodegradable MNPs can be designed to facilitate drug delivery, influence disease diagnostics, facilitate tissue regeneration and permit protein purification. Because of their limited toxicity, MNPs are widely used in theranostics, simultaneously facilitating diagnostics and therapeutics. To realize therapeutic end points, iron oxide nanoparticle cores (5-30 nm) are encapsulated in a biocompatible polymer shell with drug cargos. Although limited, the toxic potential of MNPs parallels magnetite composition, along with shape, size and surface chemistry. Clearance is hastened by the reticuloendothelial system. To surmount translational barriers, the crystal structure, particle surface and magnetic properties of MNPs need to be optimized. With this in mind, we provide a comprehensive evaluation of advancements in MNP synthesis, functionalization and design, with an eye towards bench-to-bedside translation.
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Affiliation(s)
- Dhirender Singh
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE, USA
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22
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Sedlacik M, Pavlinek V. A tensiometric study of magnetorheological suspensions' stability. RSC Adv 2014. [DOI: 10.1039/c4ra11842a] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Surface free energy and sedimentation of composite particles with unchanged magnetorheological properties and improved resistance against thermal oxidation and chemical degradation is determined via tensiometry.
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Affiliation(s)
- M. Sedlacik
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- Zlin, Czech Republic
| | - V. Pavlinek
- Centre of Polymer Systems
- University Institute
- Tomas Bata University in Zlin
- Zlin, Czech Republic
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24
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Machovsky M, Mrlik M, Kuritka I, Pavlinek V, Babayan V. Novel synthesis of core–shell urchin-like ZnO coated carbonyl iron microparticles and their magnetorheological activity. RSC Adv 2014. [DOI: 10.1039/c3ra44982c] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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25
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Richardi J, Weis JJ. Influence of short range potential on field induced chain aggregation in low density dipolar particles. J Chem Phys 2013; 138:244704. [DOI: 10.1063/1.4811290] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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26
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Bica I, Liu YD, Choi HJ. Physical characteristics of magnetorheological suspensions and their applications. J IND ENG CHEM 2013. [DOI: 10.1016/j.jiec.2012.10.008] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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27
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Viota JL, Carazo A, Munoz-Gamez JA, Rudzka K, Gómez-Sotomayor R, Ruiz-Extremera A, Salmerón J, Delgado AV. Functionalized magnetic nanoparticles as vehicles for the delivery of the antitumor drug gemcitabine to tumor cells. Physicochemical in vitro evaluation. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2012; 33:1183-92. [PMID: 23827558 DOI: 10.1016/j.msec.2012.12.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 08/23/2012] [Accepted: 12/02/2012] [Indexed: 12/24/2022]
Abstract
Gemcitabine is a chemotherapy drug used in different carcinomas, although because it displays a short biological half-life, its plasmatic levels can quickly drop below the effective threshold. Nanoparticle-based drug delivery systems can provide an alternative approach for regulating the bioavailability of this and most other anticancer drugs. In this work we describe a new model of composite nanoparticles consisting of a core of magnetite nanoparticles, coated with successive layers of high molecular weight poly(acrylic acid) and chitosan, and a final layer of folic acid. The possibility of using these self-assembled nanostructures for gemcitabine vehiculization is explored. First, the surface charge of the composite particles is studied by means of electrophoretic mobility measurements as a function of pH for poly(acrylic acid) (carbopol) of different molecular weights. The adsorption of folic acid, aimed at increasing the chances of the particles to pass the cell membrane, is followed up by optical absorbance measurements, which were also employed for drug adsorption determinations. As a main result, it is shown that gemcitabine adsorbs onto the surface of chitosan/carbopol-coated magnetite nanoparticles. In vitro experiments show that the functionalized magnetic nanoparticles are able to deliver the drug to the nuclei of liver, colon and breast tumor cells.
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Affiliation(s)
- J L Viota
- Networked Biomedical Research Center for Hepatic and Digestive Diseases (CIBERehd), Hospital Universitario San Cecilio, 18012, Granada, Spain
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28
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Reddy LH, Arias JL, Nicolas J, Couvreur P. Magnetic nanoparticles: design and characterization, toxicity and biocompatibility, pharmaceutical and biomedical applications. Chem Rev 2012; 112:5818-78. [PMID: 23043508 DOI: 10.1021/cr300068p] [Citation(s) in RCA: 1101] [Impact Index Per Article: 91.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- L Harivardhan Reddy
- Laboratoire de Physico-Chimie, Pharmacotechnie et Biopharmacie, Université Paris-Sud XI, UMR CNRS, Faculté de Pharmacie, IFR, Châtenay-Malabry, France
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29
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Masoudi A, Madaah Hosseini HR, Shokrgozar MA, Ahmadi R, Oghabian MA. The effect of poly(ethylene glycol) coating on colloidal stability of superparamagnetic iron oxide nanoparticles as potential MRI contrast agent. Int J Pharm 2012; 433:129-41. [DOI: 10.1016/j.ijpharm.2012.04.080] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Revised: 04/13/2012] [Accepted: 04/21/2012] [Indexed: 10/28/2022]
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30
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Louie SM, Phenrat T, Small MJ, Tilton RD, Lowry GV. Parameter identifiability in application of soft particle electrokinetic theory to determine polymer and polyelectrolyte coating thicknesses on colloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:10334-10347. [PMID: 22708677 DOI: 10.1021/la301912j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Soft particle electrokinetic models have been used to determine adsorbed nonionic polymer and polyelectrolyte layer properties on nanoparticles or colloids by fitting electrophoretic mobility data. Ohshima first established the formalism for these models and provided analytical approximations ( Ohshima, H. Adv. Colloid Interface Sci.1995, 62, 189 ). More recently, exact numerical solutions have been developed, which account for polarization and relaxation effects and require fewer assumptions on the particle and soft layer properties. This paper characterizes statistical uncertainty in the polyelectrolyte layer charge density, layer thickness, and permeability (Brinkman screening length) obtained from fitting data to either the analytical or numerical electrokinetic models. Various combinations of particle core and polymer layer properties are investigated to determine the range of systems for which this analysis can provide a solution with reasonably small uncertainty bounds, particularly for layer thickness. Identifiability of layer thickness in the analytical model ranges from poor confidence for cases with thick, highly charged coatings, to good confidence for cases with thin, low-charged coatings. Identifiability is similar for the numerical model, except that sensitivity is improved at very high charge and permeability, where polarization and relaxation effects are significant. For some poorly identifiable cases, parameter reduction can reduce collinearity to improve identifiability. Analysis of experimental data yielded results consistent with expectations from the simulated theoretical cases. Identifiability of layer charge density and permeability is also evaluated. Guidelines are suggested for evaluation of statistical confidence in polymer and polyelectrolyte layer parameters determined by application of the soft particle electrokinetic theory.
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Affiliation(s)
- Stacey M Louie
- Center for the Environmental Implications of NanoTechnology, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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31
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Rodríguez-Arco L, López-López MT, Durán JDG, Zubarev A, Chirikov D. Stability and magnetorheological behaviour of magnetic fluids based on ionic liquids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:455101. [PMID: 21971064 DOI: 10.1088/0953-8984/23/45/455101] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This paper reports the preparation of magnetic fluids consisting of magnetite nanoparticles dispersed in an ionic liquid. Different additives were used in order to stabilize the fluids. Colloidal stability was checked by magnetic sedimentation, centrifugation and direct observation. The results of these tests showed that a true ferrofluid was only obtained when the nanoparticles were coated with a layer of surfactant compatible with the ionic liquid. These experiments also showed that stability could not be reached just by electrostatic repulsion. The conclusions of the stability tests were confirmed by calculations of the interparticle energies of interaction. The rheological behaviour of the magnetic fluids upon magnetic field application was also investigated. The experimental magnetoviscous response was fitted by a microstructural model. The model considered that the fluids consisted of two populations of particles, one with a magnetic core diameter of 9 nm, and another with a larger diameter. Upon field application chain-like structures are supposed to be induced. According to estimations particles of 9 nm are too small to aggregate upon field application. The results of the calculations showed that the intensity of the magnetoviscous response depends on the concentration and size of the large particles, and on the thickness of the surfactant layers.
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Affiliation(s)
- Laura Rodríguez-Arco
- Department of Applied Physics, University of Granada, Avenida Fuentenueva s/n, 18071, Granada, Spain
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32
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Fang FF, Liu YD, Choi HJ, Seo Y. Core-shell structured carbonyl iron microspheres prepared via dual-step functionality coatings and their magnetorheological response. ACS APPLIED MATERIALS & INTERFACES 2011; 3:3487-3495. [PMID: 21815626 DOI: 10.1021/am200714p] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The dispersion stability of soft magnetic carbonyl iron (CI)-based magnetorheological (MR) fluids was improved by applying a unique functional coating composed of a conducting polyaniline layer and a multiwalled carbon nanotube nest to the surfaces of the CI particles via conventional dispersion polymerization, followed by facile solvent casting. The coating morphology and thickness were analyzed by SEM and TEM imaging. Chemical composition of the polyaniline layer was detected by Raman spectroscope, which also confirmed the coating performance successfully. The influence of the functional coating on the magnetic properties was investigated by measuring the MR performance and sedimentation properties using a vibrating sample magnetometer, rotational rheometer, and Turbiscan apparatus. Improved dispersion characteristics of the MR fluid were observed.
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Affiliation(s)
- Fei Fei Fang
- Department of Polymer Science and Engineering, Inha University, Incheon 402-751, Korea
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33
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Viota JL, Rudzka K, Trueba Á, Torres-Aleman I, Delgado ÁV. Electrophoretic characterization of insulin growth factor (IGF-1) functionalized magnetic nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:6426-6432. [PMID: 21506536 DOI: 10.1021/la2009144] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The synthesis of composite nanoparticles consisting of a magnetite core coated with a layer of the hormone insulin growth factor 1 (IGF-1) is described. The adsorption of the hormone in the different formulations is first studied by electrophoretic mobility measurements as a function of pH, ionic strength, and time. Because of the permeable character expected for both citrate and IGF-1 coatings surrounding the magnetite cores, an appropriate analysis of their electrophoretic mobility must be addressed. Recent developments of electrokinetic theories for particles covered by soft surface layers have rendered possible the evaluation of the softness degree from raw electrophoretic mobility data. In the present contribution, the data are quantitatively analyzed based on the theoretical model of the electrokinetics of soft particles. As a result, information is obtained on both the thickness and the charge density of the surrounding layer. It is shown that IGF-1 adsorbs onto the surface of citrate-coated magnetite nanoparticles, and adsorption is confirmed by dot-blot analysis. In addition, it is also demonstrated that the external layer of IGF-1 exerts a shielding effect on the surface charge of citrate-magnetite particles, as suggested by the mobility reduction upon contacting the particles with the hormone. Aging effects are demonstrated, providing an electrokinetic fingerprint of changes in adsorbed protein configuration with time.
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Affiliation(s)
- Julián L Viota
- Department of Physics, Campus Las Lagunillas, University of Jaén, 23071, Jaén, Spain.
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34
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Abstract
Based on the uniformity of magnetic field in shear circle, low magnetic field, and inconvenient of injecting magnetorheological fluid (MRF), the rotational parallel disk instrument for measuring the shear stress of MRF made by ourselves was improved. The magnetic circuit of the instrument was optimized using Ansys software, the parts and structure of leaking magnetic field were improved, and the uniformity of the magnetic field in shear circle plates was strengthen; when the current was 1.65A, the average magnetic field in shear circle plates was 0.9T. Then the influence on MRF by using different mass fractions of nano-Fe3O4 was researched, which indicate when the ration between the mass of nano-Fe3O4 and that of carbonyl iron particles is 5%, the characteristic of MRF is best.
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Zeltner M, Schätz A, Hefti ML, Stark WJ. Magnetothermally responsive C/Co@PNIPAM-nanoparticles enable preparation of self-separating phase-switching palladium catalysts. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm03338c] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Golas PL, Louie S, Lowry GV, Matyjaszewski K, Tilton RD. Comparative study of polymeric stabilizers for magnetite nanoparticles using ATRP. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16890-16900. [PMID: 20945936 DOI: 10.1021/la103098q] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A series of polyelectrolytes with controlled molecular weight, a narrow chain-length distribution, and systematic structural differences were synthesized using atom-transfer radical polymerization and investigated as stabilizers for magnetite nanoparticles in aqueous suspensions. Structural differences include the degree of polymerization, the chain architecture, and the identity of the charged functional unit. The synthesized polymers are sulfonated poly(2-hydroxyethyl methacrylate), a block copolymer of the former with poly(n-butyl methacrylate), poly(sodium styrene sulfonate), poly(sodium acrylate), and poly(sodium vinylphosphonate). The colloidal stability is assessed by measuring the fraction of particles, based on turbidity, that sediment after a period of time at increasing ionic strength. Sedimentation results are complimented by dynamic light scattering determinations of the hydrodynamic diameter of the particles that remain suspended. When adsorption and sedimentation are conducted at high pH, poly(sodium acrylate) and poly(sodium vinylphosphonate) yield the most stable suspensions because of their strong coordinative interactions with the iron oxide surface. At low pH, the polymers that retain pendant negative charges (each of the sulfonated polymers) yield high stable fractions at all ionic strengths investigated up to 100 mM (NaCl), whereas polyelectrolytes that become protonated with decreasing pH, poly(sodium acrylate) and poly(sodium vinylphosphonate), lose their stabilizing capacity even at low ionic strengths. The chain-length distribution profoundly alters a polymer's stabilization tendencies. Two poly(sodium acrylate) samples with the same number-average molecular weight but widely different chain-length distributions proved to have opposite tendencies, with the polydisperse sample being a good stabilizer and the low polydispersity one being a strong flocculant. This investigation provides guidelines for the design of polymeric stabilizers for magnetite nanoparticles according to the pH and ionic strength of the intended application.
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Affiliation(s)
- Patricia L Golas
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
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37
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Phenrat T, Song JE, Cisneros CM, Schoenfelder DP, Tilton RD, Lowry GV. Estimating attachment of nano- and submicrometer-particles coated with organic macromolecules in porous media: development of an empirical model. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:4531-4538. [PMID: 20465214 DOI: 10.1021/es903959c] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Assessing the environmental transport and fate of manufactured nanoparticles (NPs) and potential exposure risks requires models for predicting attachment of NPs coated with organic macromolecules in porous media. The objective of this study was to determine the properties of coated nanoparticles that control their attachment behavior. Deposition data for a variety of nanoparticles with different types of anionic organic coatings, including natural organic matter (NOM)-coated latex and hematite nanoparticles, and poly(styrenesulfonate)-, carboxymethylcellulose-, and polyaspartate-coated hematite and titanium dioxide nanoparticles (80 data points), were used to develop an empirical correlation between measurable NP properties and their sticking coefficient (alpha) under a variety of electrolyte conditions and flow velocities. Available semiempirical correlations used to predict the attachment efficiency of electrostatically stabilized (uncoated) NPs overestimate the attachment efficiency of nanoparticles coated with NOM or synthetic polyelectrolytes because the correlations neglect electrosteric repulsions and the decreased friction afforded by such coatings that can inhibit attachment to surfaces. Adding a dimensionless parameter (N(LEK)) representing steric repulsions and the decreased friction force afforded by adsorbed NOM or anionic polyelectrolytes in the correlation significantly improves the correlation. This establishes the importance of including the adsorbed NOM- or polyelectrolyte layer properties for estimating the attachment efficiency of NPs in the environment. The form of N(LEK) suggests that limiting unintended transport and exposure to NPs could be achieved by using coatings with the smallest adsorbed mass and polymer density, shortest extended layer thickness, and largest molecular weight that would still afford the desired functionality of the coating.
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Affiliation(s)
- Tanapon Phenrat
- Center for Environmental Implications of Nanotechnology, Department of Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213-3890, USA
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38
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Zhang Y, Li Q, Sun L, Tang R, Zhai J. High efficient removal of mercury from aqueous solution by polyaniline/humic acid nanocomposite. JOURNAL OF HAZARDOUS MATERIALS 2010; 175:404-409. [PMID: 19896766 DOI: 10.1016/j.jhazmat.2009.10.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Revised: 09/06/2009] [Accepted: 10/05/2009] [Indexed: 05/28/2023]
Abstract
A composite sorbent PANI/HA was prepared by adding humic acid (HA) into chemical oxidation process of polyaniline (PANI). The sorbent was characterized by BET analysis, transmission electron microscopy, and FT-IR spectra. Batch adsorption results showed that the sorbent had high affinity to Hg(II) in aqueous solutions. The adsorption kinetics results of Hg(II) showed that the adsorption reached equilibrium within 200 min and adsorption rates could be described by pseudo-second-order kinetics. Sorption of Hg(II) to PANI/HA agreed well to the Langmuir adsorption model at different ionic strengths with the maximum adsorption capacity of 671 mg g(-1) (I=0.20 M). The experimental results showed solution pH values had a major impact on Hg(II) adsorption and with the help of HA the sorbent can effectively remove Hg(II) in a wide pH range (pH 4-7.5). An adsorption mechanism was proposed based on the XPS results.
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Affiliation(s)
- Ya Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
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Fang FF, Choi HJ, Seo Y. Sequential coating of magnetic carbonyliron particles with polystyrene and multiwalled carbon nanotubes and its effect on their magnetorheology. ACS APPLIED MATERIALS & INTERFACES 2010; 2:54-60. [PMID: 20356220 DOI: 10.1021/am900577w] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A two-step process for the sequential coating of magnetic carbonyliron (CI) particles with polystyrene (PS) and multiwalled carbon nanotubes (MWCNTs) was used to improve the sedimentation stability of micrometer-sized magnetic CI particles for magnetorheological (MR) applications under an applied magnetic field. The CI particles were initially coated with nanosized PS beads using an in situ dispersion polymerization method and then wrapped with a dense MWCNT nest through a solvent-casting method in a water/oil emulsion system. The morphology, MR performance, and sedimentation stability of the synthesized magnetic composite particles were examined. The composite particles showed enhanced MR characteristics and dispersion stability.
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Affiliation(s)
- Fei Fei Fang
- Department of Polymer Science and Engineering, Inha University, Incheon 402-751, Korea
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Viota JL, Durán JDG, Delgado AV. Study of the magnetorheology of aqueous suspensions of extremely bimodal magnetite particles. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2009; 29:87-94. [PMID: 19430949 DOI: 10.1140/epje/i2009-10453-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 02/05/2009] [Accepted: 03/13/2009] [Indexed: 05/27/2023]
Abstract
In this paper we describe the magnetorheological behavior of aqueous suspensions consisting of magnetite particles of two size populations, in the micrometer and nanometer scale, respectively. Previous works on the magnetorheology of oil-based fluids demonstrated that the addition of nanoparticles has a very significant effect on the intensity of the magnetorheological effect. The present contribution confirms such results in the case of aqueous fluids, based on the dependence of the yield stress and the viscosity of the bimodal suspensions on both the composition of the mixtures and the magnetic field strength. It is demonstrated that for a given concentration of micrometer particles, increasing the amount of nanometer magnetite provokes a clear enhancement in the yield stress for all the magnetic fields applied. This is proposed to be due to the formation of heterogeneous aggregates that improve the stability of the suspensions and ease the building of well-arranged field-induced structures. The behavior of both the yield stress and the post-yield viscosity agrees better with the predictions of standard chain models when the relative proportion of both types of particles confers optimum stability to the bimodal dispersions.
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Affiliation(s)
- J L Viota
- Department of Physics, University of Jaén, 23071, Jaén, Spain
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42
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López-Viota J, Mandal S, Delgado AV, Toca-Herrera JL, Möller M, Zanuttin F, Balestrino M, Krol S. Electrophoretic characterization of gold nanoparticles functionalized with human serum albumin (HSA) and creatine. J Colloid Interface Sci 2009; 332:215-23. [DOI: 10.1016/j.jcis.2008.11.077] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 11/25/2008] [Accepted: 11/27/2008] [Indexed: 11/25/2022]
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43
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Functionalized gold nanoparticles: Synthesis, structure and colloid stability. J Colloid Interface Sci 2009; 331:251-62. [DOI: 10.1016/j.jcis.2008.12.002] [Citation(s) in RCA: 314] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 11/24/2008] [Accepted: 12/02/2008] [Indexed: 11/19/2022]
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44
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Viota J, Delgado A, Arias J, Durán J. Study of the magnetorheological response of aqueous magnetite suspensions stabilized by acrylic acid polymers. J Colloid Interface Sci 2008; 324:199-204. [DOI: 10.1016/j.jcis.2008.05.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 05/14/2008] [Accepted: 05/16/2008] [Indexed: 10/22/2022]
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45
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López-López MT, Gómez-Ramírez A, Durán JDG, González-Caballero F. Preparation and characterization of iron-based magnetorheological fluids stabilized by addition of organoclay particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7076-7084. [PMID: 18540642 DOI: 10.1021/la703519p] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Suspensions of micrometer-sized iron particles (10 vol %) dispersed in kerosene and stabilized by addition of organoclay particles were prepared. The magnetization curves of these suspensions were measured, and their sedimentation and redispersion behaviors were analyzed as a function of clay concentration by means of optical and rheological methods. Furthermore, their magnetorheological properties were investigated using a controlled rate magnetorheometer and the effect of clay concentration on these properties was also analyzed. These experiments showed that the addition of clay slows down iron particle settling and eases the redispersion of the iron-based suspensions without masking their magnetorheological properties. Two mechanisms were found to be involved in this behavior: (i) the formation of a clay gel network and (ii) the presence of heterogeneous iron-clay adhesion.
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Affiliation(s)
- Modesto T López-López
- Department of Applied Physics, Faculty of Sciences, University of Granada, Avda Fuentenueva s/n, 18071 Granada, Spain.
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46
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Vereda F, de Vicente J, Hidalgo-Álvarez R. Colloidal characterization of micron-sized rod-like magnetite particles. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2007.06.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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47
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Galindo-Gonzalez C, Iglesias G, González-Caballero F, Durán J. Stability of concentrated aqueous clay–magnetite suspensions. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2006.12.076] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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48
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Zhang Q, Thompson MS, Carmichael-Baranauskas AY, Caba BL, Zalich MA, Lin YN, Mefford OT, Davis RM, Riffle JS. Aqueous dispersions of magnetite nanoparticles complexed with copolyether dispersants: experiments and theory. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:6927-36. [PMID: 17521205 DOI: 10.1021/la070116+] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Magnetite (Fe3O4) nanoparticles have been synthesized and complexed with carboxylate-functional block copolymers, and then aqueous dispersions of the complexes were investigated as functions of their chemical and morphological structures. The block copolymer dispersants had either poly(ethylene oxide), poly(ethylene oxide-co-propylene oxide), or poly(ethylene oxide-b-propylene oxide) outer blocks, and all of them had a polyurethane center block that contained pendent carboxylate groups. The complexes were formed through interactions of the carboxylates with the surfaces of the magnetite nanoparticles. The magnetite cores of the magnetite-copolymer complexes were near 10 nm in diameter, and the particles were superparamagnetic. Complexes with mass ratios of polymer to magnetite varying from 50:50 to 85:15 were studied. One of our objectives is to design complexes that form stable dispersions of discrete particles in water, yet that can be actuated (moved together) upon exposure to a uniform magnetic field. DLVO calculations that accounted for magnetic attractive interparticle forces, as well as van der Waals, steric, and electrostatic forces are presented. Compositions were identified wherein a shallow, attractive interparticle potential minimum appears once the magnetic term is applied. This suggests that it may be possible to tune the structures of superparamagnetic nanoparticle shells to allow discrete dispersions without a field, yet weak flocculation could be induced upon exposure to a field.
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Affiliation(s)
- Qian Zhang
- The Macromolecules and Interfaces Institute, Virginia Tech, Blacksburg, VA 24061, USA
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Viota JL, González-Caballero F, Durán JDG, Delgado AV. Study of the colloidal stability of concentrated bimodal magnetic fluids. J Colloid Interface Sci 2007; 309:135-9. [PMID: 17346730 DOI: 10.1016/j.jcis.2007.01.066] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 01/24/2007] [Accepted: 01/24/2007] [Indexed: 10/23/2022]
Abstract
In this paper, we describe an investigation of the stability and sedimentation behavior of moderately concentrated suspensions of extremely bimodal magnetite particles, including micro- (diameter 1450 nm) and nano- (diameter 8 nm) units. An original method is used, based on the determination of the time dependence of the inductance of a coil surrounding the suspensions. The method proves to be very useful for the determination of the volume fraction of magnetic material in the sensed volume. The observed changes in the resonant frequency of a parallel LC circuit demonstrate that the addition of the magnetite nanoparticles improves the stability and slows down the settling rate of the mixed suspensions. It is proposed that the observed behavior is the result of competition between two processes. One is the formation of a cloud of nanoparticles around the large magnetite units, by virtue of which the latter are maintained at distances beyond the range of DLVO and magnetic attractive interactions. At long times, these composite units will eventually sediment when some critical size is reached, as the small particles are progressively associated with the large ones. The second mechanism is mainly predominant at short times and is related to the higher viscosity of the dispersion medium (the nanoparticles dispersed in the base fluid) for higher nanoparticle concentrations. The stability of the suspensions is discussed in terms of the competition between the two mechanisms.
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Affiliation(s)
- J L Viota
- Department of Applied Physics, School of Sciences, University of Granada, 18071 Granada, Spain
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Erdemoğlu M, Sarikaya M. Effects of heavy metals and oxalate on the zeta potential of magnetite. J Colloid Interface Sci 2006; 300:795-804. [PMID: 16707134 DOI: 10.1016/j.jcis.2006.04.004] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 04/01/2006] [Accepted: 04/04/2006] [Indexed: 11/30/2022]
Abstract
Zeta potential is a function of surface coverage by charged species at a given pH, and it is theoretically determined by the activity of the species in solution. The zeta potentials of particles occurring in soils, such as clay and iron oxide minerals, directly affect the efficiency of the electrokinetic soil remediation. In this study, zeta potential of natural magnetite was studied by conducting electrophoretic mobility measurements in single and binary solution systems. It was shown that adsorption of charged species of Co(2+), Ni(2+), Cu(2+), Zn(2+), Pb(2+), and Cd(2+) and precipitation of their hydroxides at the mineral surface are dominant processes in the charging of the surface in high alkaline suspensions. Taking Pb(2+) as an example, three different mechanisms were proposed for its effect on the surface charge: if pH<5, competitive adsorption with H(3)O(+); if 5<pH<6, adsorption and surface precipitation; and if pH>6, precipitation of heavy metal hydroxides prevails. Oxalate anion changed the associated surface charge by neutralizing surface positive charges by complexing with iron at the surface, and ultimately reversed the surface to a negative zeta potential. Therefore the adsorption ability of heavy metal ions ultimately changed in the presence of oxalate ion. The changes in the zeta potentials of the magnetite suspensions with solution pH before and after adsorption were utilized to estimate the adsorption ability of heavy metal ions. The mechanisms for heavy metals and oxalate adsorption on magnetite were discussed in the view of the experimental results and published data.
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Affiliation(s)
- Murat Erdemoğlu
- Department of Mining Engineering, Engineering Faculty, Inönü University, 44280 Malatya, Turkey.
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