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Godek E, Grządka E, Maciołek U. Comparison of the influence of cationic polysaccharides on the stability properties of montmorillonite suspensions in the presence of sodium dodecyl sulphate. Carbohydr Polym 2022; 278:118985. [PMID: 34973792 DOI: 10.1016/j.carbpol.2021.118985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/17/2021] [Accepted: 12/02/2021] [Indexed: 12/01/2022]
Abstract
The mixtures of cationic cellulose (CC) or cationic guar gum (CGG) with the anionic sodium dodecyl sulfate surfactant (SDS) were used as stabilizers for the aqueous suspensions of montmorillonite (Mt). The stabilization processes and the stabilization mechanism were investigated using the UV-VIS. The obtained results show that both polysaccharides can be used as stabilizers of the water suspensions of montmorillonite due to the effective adsorption of CC and CGG with or without SDS on the Mt. surface. To obtain complete information on the studied systems, the additional measurements of the surface tension, zeta potential, FT-IR, XRD and SEM were made. The results prove that the intermolecular complexes formed between the polysaccharides and SDS can adsorb on the Mt. surface, change the structure of the electrical double layer and the stability properties of the studied suspensions.
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Affiliation(s)
- E Godek
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. Skłodowskiej - Curie 3 Sq., 20-031 Lublin, Poland.
| | - E Grządka
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. Skłodowskiej - Curie 3 Sq., 20-031 Lublin, Poland.
| | - U Maciołek
- Analytical Laboratory, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. Skłodowskiej - Curie 3 Sq., 20-031 Lublin, Poland.
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2
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Grządka E, Matusiak J, Godek E. Alginic acid as a stabilizer of zirconia suspensions in the presence of cationic surfactants. Carbohydr Polym 2020; 246:116634. [PMID: 32747269 DOI: 10.1016/j.carbpol.2020.116634] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 11/26/2022]
Abstract
The influence of hydrocarbon (CTAB), fluorocarbon (S-106-A) and silicone (C-Si) cationic surfactants: on stability, adsorption and electrokinetic properties of the alginic acid (AA)/zirconia (ZrO2) suspensions was studied. The results obtained from the spectrophotometric measurements indicate on very high effectiveness of the surfactants in stabilization of the studied systems. This is due to the formation of multimolecular complexes between alginic acid and the surfactants. The existence of these complexes was confirmed by the surface tension and the zeta potential measurements. Presented studies also enabled the estimation of the conditions under which the complexes are effectively created and the determination of their character. These findings were also confirmed by the adsorption data. Moreover, the surface charge density measurements proved that the adsorption of AA or the AA/surfactant complexes changes the structure of the electrical double layer. The presented results may find applications in the fields of functionalized materials.
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Affiliation(s)
- E Grządka
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. Skłodowskiej - Curie 3 Sq., 20-031, Lublin, Poland.
| | - J Matusiak
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. Skłodowskiej - Curie 3 Sq., 20-031, Lublin, Poland.
| | - E Godek
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Skłodowska University, M. Skłodowskiej - Curie 3 Sq., 20-031, Lublin, Poland.
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3
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Matusiak J, Grządka E, Kowalczuk A, Pietruszka R, Godlewski M. The influence of hydrocarbon, fluorinated and silicone surfactants on the adsorption, stability and electrokinetic properties of the κ-carrageenan/alumina system. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Bodratti AM, Sarkar B, Alexandridis P. Adsorption of poly(ethylene oxide)-containing amphiphilic polymers on solid-liquid interfaces: Fundamentals and applications. Adv Colloid Interface Sci 2017; 244:132-163. [PMID: 28069108 DOI: 10.1016/j.cis.2016.09.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 09/23/2016] [Accepted: 09/23/2016] [Indexed: 12/30/2022]
Abstract
The adsorption of amphiphilic molecules of varying size on solid-liquid interfaces modulates the properties of colloidal systems. Nonionic, poly(ethylene oxide) (PEO)-based amphiphilic molecules are particularly useful because of their graded hydrophobic-hydrophilic nature, which allows for adsorption on a wide array of solid surfaces. Their adsorption also results in other useful properties, such as responsiveness to external stimuli and solubilization of hydrophobic compounds. This review focuses on the adsorption properties of PEO-based amphiphiles, beginning with a discussion of fundamental concepts pertaining to the adsorption of macromolecules on solid-liquid interfaces, and more specifically the adsorption of PEO homopolymers. The main portion of the review highlights studies on factors affecting the adsorption and surface self-assembly of PEO-PPO-PEO block copolymers, where PPO is poly(propylene oxide). Block copolymers of this type are commercially available and of interest in several fields, due to their low toxicity and compatibility in aqueous systems. Examples of applications relevant to the interfacial behavior of PEO-PPO-PEO block copolymers are paints and coatings, detergents, filtration, and drug delivery. The methods discussed herein for manipulating the adsorption properties of PEO-PPO-PEO are emphasized for their ability to shed light on molecular interactions at interfaces. Knowledge of these interactions guides the formulation of novel materials with useful mesoscale organization and micro- and macrophase properties.
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Chibowski S, Paszkiewicz M, Wiśniewska M. The Influence of Surfactant (SDS) on the Adsorption Properties of Polyvinyl Alcohol and Polyethylene Glycol in an Alumina/Solution System. ADSORPT SCI TECHNOL 2016. [DOI: 10.1260/026361702321039500] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The influence of sodium dodecyl sulphate (SDS) on the adsorption properties of non-ionic polymers, i.e. polyethylene glycol (PEG) and polyvinyl alcohol (PVA), at the Al2O3/solution interface was studied. Measurements for various molecular weights and for various amounts of functional groups on the polymer macromolecules were undertaken and the results obtained discussed in the light of these variations. Studies of the mutual interactions of the polymer–surfactant system in aqueous solution were helpful in explaining the equilibria involved in the Al2O3/polymer solution system in the presence of SDS. The thickness of the adsorption layer was determined by viscometric methods and the influence of the degree of hydrolysis of PVA on the structure of the adsorption layer demonstrated.
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Affiliation(s)
- S. Chibowski
- Department of Radiochemistry and Colloid Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, M. Curie Skłodowska Sq. 3, 20-031 Lublin, Poland
| | - M. Paszkiewicz
- Department of Radiochemistry and Colloid Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, M. Curie Skłodowska Sq. 3, 20-031 Lublin, Poland
| | - M. Wiśniewska
- Department of Radiochemistry and Colloid Chemistry, Faculty of Chemistry, Maria Curie-Skłodowska University, M. Curie Skłodowska Sq. 3, 20-031 Lublin, Poland
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Zheng Y, Wyman IW. Supramolecular Nanostructures Based on Cyclodextrin and Poly(ethylene oxide): Syntheses, Structural Characterizations and Applications for Drug Delivery. Polymers (Basel) 2016; 8:E198. [PMID: 30979290 PMCID: PMC6431930 DOI: 10.3390/polym8050198] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 05/10/2016] [Accepted: 05/10/2016] [Indexed: 11/16/2022] Open
Abstract
Cyclodextrins (CDs) have been extensively studied as drug delivery carriers through host⁻guest interactions. CD-based poly(pseudo)rotaxanes, which are composed of one or more CD rings threading on the polymer chain with or without bulky groups (or stoppers), have attracted great interest in the development of supramolecular biomaterials. Poly(ethylene oxide) (PEO) is a water-soluble, biocompatible polymer. Depending on the molecular weight, PEO can be used as a plasticizer or as a toughening agent. Moreover, the hydrogels of PEO are also extensively studied because of their outstanding characteristics in biological drug delivery systems. These biomaterials based on CD and PEO for controlled drug delivery have received increasing attention in recent years. In this review, we summarize the recent progress in supramolecular architectures, focusing on poly(pseudo)rotaxanes, vesicles and supramolecular hydrogels based on CDs and PEO for drug delivery. Particular focus will be devoted to the structures and properties of supramolecular copolymers based on these materials as well as their use for the design and synthesis of supramolecular hydrogels. Moreover, the various applications of drug delivery techniques such as drug absorption, controlled release and drug targeting based CD/PEO supramolecular complexes, are also discussed.
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Affiliation(s)
- Yue Zheng
- Department of internal medicine, The First Hospital in Qinhuangdao Affiliated to Hebei Medical University, Qinhuangdao 066004, China.
| | - Ian W Wyman
- Department of Chemistry, Queen's University, Kingston, ON K7L 3N6, Canada.
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7
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Suspension “click” polymerizations: thiol-ene polymer particles prepared with natural gum stabilizers. Colloid Polym Sci 2015. [DOI: 10.1007/s00396-015-3628-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Ye L, Xie Y, Qiu D, Kan Y, Zhang ZD. Particle shape dependence of rheological behavior for colloid-polymer mixtures. CHINESE JOURNAL OF POLYMER SCIENCE 2014. [DOI: 10.1007/s10118-014-1538-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Lone S, Ahn JI, Kim MR, Lee HM, Kim SH, Lodge TP, Cheong IW. Photoresponsive phase separation of a poly(NIPAAm-co-SPO-co-fluorophore) random copolymer in W/O droplet. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:9577-9583. [PMID: 25046025 DOI: 10.1021/la5022005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The photoresponsive phase separation of a poly(N-isopropylacrylamide-co-spironaphthoxazine methacryloyl-co-allyl-2-(2,6-bis((E)-4-(diphenylamino)styryl)-4H-pyran-4-ylidene)-2-cyanoacetate) random copolymer, i.e., poly(NIPAAm-co-SPO-co-fluorophore), in water-in-oil (W/O) droplets is described. The photoresponsive aqueous droplets were generated in the coflow regime of a simple tubular microfluidic device. The phase separation of the copolymer in the W/O droplets was induced by UV light at 365 nm and was affected significantly by the presence of 2,2-diethoxyacetophenone (DEAP) and sorbitan monooleate (Span 80). When the droplets were subjected to UV irradiation for more than 2 min, the phase-separated copolymer was transferred completely from the aqueous droplet to the continuous phase of hexadecane. The phase separation arises from the photoisomerization shifting the spiro to the merocyanine form of the SPO pendant group in the copolymer, which in turn reduces the hydrophilicity of the copolymer via attractive hydrogen-bonding interactions between the merocyanine group and hydrophobic additives, i.e., Span 80, DEAP, and some stable fragments derived from the photocleavage of DEAP under UV irradiation. These interactions cause the copolymer to associate with the additives and then accelerate the phase separation of the copolymer and subsequent phase transfer of copolymer aggregates. The separate effects of DEAP and Span 80 were also investigated by UV spectrophotometric analysis of the rate coefficient of the reverse transformation (merocyanine to spiro) of the photochromic monomer. We propose a mechanism of phase separation of the copolymer in the W/O droplet based on the NMR and GC-MASS analyses of DEAP.
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Affiliation(s)
- Saifullah Lone
- Department of Applied Chemistry and ‡Department of Textile System Engineering, Kyungpook National University , Daegu 702-701, South Korea
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10
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de Vos WM, Cattoz B, Avery MP, Cosgrove T, Prescott SW. Adsorption and surfactant-mediated desorption of poly(vinylpyrrolidone) on plasma- and piranha-cleaned silica surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:8425-8431. [PMID: 25007346 DOI: 10.1021/la501877v] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Optical flow cell reflectometry was used to study the adsorption of poly(vinylpyrrolidone) (PVP) to a silica surface and the subsequent surfactant adsorption and polymer desorption upon exposure to the anionic surfactant sodium dodecyl sulfate (SDS). We have studied these effects as a function of pH and surfactant concentration, but also for two different methods of silica preparation, O2 plasma and piranha cleaning. As a function of pH, a plateau in the amount adsorbed of ∼0.6 mg/m(2) is observed below a critical pH, above which the adsorption decreases to zero within 2-3 pH units. An increase in pH leads to dissociation of surface OH groups and a decreased potential for hydrogen bonding between the polymer and surface. For the plasma- and piranha-cleaned silica, the critical pH differs by 1-2 pH units, a reflection of the much larger amount of surface OH groups on piranha-cleaned silica (for a given pH). Subsequent rinsing of the adsorbed layer of PVP with an SDS solution leads to total or partial desorption of the PVP layer. Any remaining adsorbed PVP then acts as an adsorption site for SDS. A large difference between plasma- and piranha-cleaned silica is observed, with the PVP layer adsorbed to plasma-cleaned silica being much more susceptible to desorption by SDS. For a plasma-cleaned surface at pH 5.5, only 30% of the originally adsorbed PVP is remaining, while for piranha-cleaned silica, the pH can be increased to 10 before a similar reduction in the amount of adsorbed PVP is seen. For a given pH, piranha-cleaned silica has a higher surface charge, leading to a smaller amount of adsorbed SDS per PVP chain on a piranha-cleaned surface compared to a plasma-cleaned surface under identical conditions. In that way, the high negative surface charge makes desorption by negatively charged SDS more difficult. The high surface charge thus protects the neutral polymer from surfactant-mediated desorption.
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Affiliation(s)
- Wiebe M de Vos
- School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
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11
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Complexation of polymeric stabilisers in solution and at the silica nanoparticle interface. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2014.02.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Durham OZ, Shipp DA. Suspension thiol-ene photopolymerization: Effect of stabilizing agents on particle size and stability. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.02.044] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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13
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Ye L, Chu X, Zhang Z, Kan Y, Xie Y, Grillo I, Zhao J, Dreiss CA, Qiu D. Effect of particle polydispersity on the structure and dynamics of complex formation between small particles and large polymer. RSC Adv 2014. [DOI: 10.1039/c4ra00929k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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14
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Sachko AV, Zakordonskii VP, Voloshinovskii AS. Fluorimetric study of the mechanism of molecular association in aqueous solutions of polymethacrylic acid and sodium dodecylbenzenesulfonate. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2013. [DOI: 10.1134/s0036024413030254] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Determination of Critical Aggregation Concentration in the Poly-(vinylpyrrolidone)–Sodium Dodecyl Sulfate System by Capillary Electrophoresis. J SURFACTANTS DETERG 2012. [DOI: 10.1007/s11743-012-1411-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Cattoz B, de Vos WM, Cosgrove T, Crossman M, Prescott SW. Manipulating interfacial polymer structures through mixed surfactant adsorption and complexation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:6282-6290. [PMID: 22435458 DOI: 10.1021/la300282m] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The effects of a nonionic alcohol ethoxylate surfactant, C(13)E(7), on the interactions between PVP and SDS both in the bulk and at the silica nanoparticle interface are studied by photon correlation spectroscopy, solvent relaxation NMR, SANS, and optical reflectometry. Our results confirmed that, in the absence of SDS, C(13)E(7) and PVP are noninteracting, while SDS interacts strongly both with PVP and C(13)E(7) . Studying interfacial interactions showed that the interfacial interactions of PVP with silica can be manipulated by varying the amounts of SDS and C(13)E(7) present. Upon SDS addition, the adsorbed layer thickness of PVP on silica increases due to Coulombic repulsion between micelles in the polymer layer. When C(13)E(7) is progressively added to the system, it forms mixed micelles with the complexed SDS, reducing the total charge per micelle and thus reducing the repulsion between micelle and the silica surface that would otherwise cause the PVP to desorb. This causes the amount of adsorbed polymer to increase with C(13)E(7) addition for the systems containing SDS, demonstrating that addition of C(13)E(7) hinders the SDS-mediated desorption of an adsorbed PVP layer.
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Affiliation(s)
- Beatrice Cattoz
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
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17
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Mohr A, Nylander T, Piculell L, Lindman B, Boyko V, Bartels FW, Liu Y, Kurkal-Siebert V. Mixtures of cationic copolymers and oppositely charged surfactants: effect of polymer charge density and ionic strength on the adsorption behavior at the silica-aqueous interface. ACS APPLIED MATERIALS & INTERFACES 2012; 4:1500-1511. [PMID: 22301772 DOI: 10.1021/am201740k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This study addresses polymer-surfactant interactions at solid-liquid interfaces and how these can be manipulated by modulating the association between ionic surfactant and oppositely charged polymer, with a particular focus on electrostatic interactions. For this purpose, the interaction of a series of cationic copolymers of vinylpyrrolidone and quaternized vinylimidazol with sodium dodecyl sulfate (SDS) at the silica-aqueous interface was followed by in situ ellipsometry. To reveal the nature of the interaction, we performed measurements for different copolyion charge densities, in the absence and presence of added salt. The path-dependence of the interaction was studied by comparing the adsorption under two different conditions, adsorption from premixed solutions and sequential addition of surfactant to the polymer solution, but the same end state. The reversibility of the adsorption process was studied by following the effect of dilution on the adsorbed layer. All copolyions adsorbed to both silica and hydrophobized silica, revealing the importance of both hydrophobic and electrostatic attractive interactions. On both types of surface, an increase in adsorbed amount was found on lowering the fraction of charged units. An increased ionic strength gave an increased adsorbed amount in all cases, but especially on hydrophobic surfaces. The adsorbed amount on silica from mixtures of the copolyions with SDS peaked at an SDS concentration corresponding closely to the concentration of cationic charges of the different polyions. Around the region of charge equivalence, there was also a phase separation in the bulk. At higher concentrations of SDS, a redissolution in the bulk, and a decrease in adsorbed amount, occurred as a result of excess SDS binding to the complexes. For the most highly charged polyions, we observed a decrease in adsorbed amount, and a shift in the adsorption maxima to lower SDS concentrations, with increasing ionic strength.
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Affiliation(s)
- Andreas Mohr
- Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University, SE-221 00 Lund, Sweden.
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18
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Tostado CP, Xu JH, Du AW, Luo GS. Experimental study on dynamic interfacial tension with mixture of SDS-PEG as surfactants in a coflowing microfluidic device. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:3120-3128. [PMID: 22250701 DOI: 10.1021/la204852w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this work, a coflowing microfluidic device was used to determine the influence of different mixed sodium dodecyl sulfate (SDS)-poly(ethylene glycol) (PEG) compound systems on dynamic interfacial tension and, by extension, corresponding emulsion droplet sizes. The aqueous solutions were used as the continuous phase in the microfluidic device, while octane was used as the organic dispersed phase. Combined SDS-PEG systems lower the interfacial tension more than either component can alone up to the critical aggregation concentration (CAC) of SDS. Octane droplet sizes produced in the microfluidic device using combined SDS-PEG systems were smaller than those produced using SDS alone, and a reduction in dynamic interfacial tension as determined by drop size followed a pattern similar to that observed in the static case (PEG4000 > PEG600 > PEG400 > PEG200 > PEG8000) with the exception of PEG8000. Finally, a previously formulated model relating interfacial tension to droplet size was used to estimate the dynamic interfacial tensions in the microfluidic device.
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Affiliation(s)
- C P Tostado
- The State Key Lab of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
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19
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Cattoz B, Cosgrove T, Crossman M, Prescott SW. Surfactant-mediated desorption of polymer from the nanoparticle interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:2485-2492. [PMID: 22188133 DOI: 10.1021/la204512d] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The surfactant-mediated desorption of adsorbed poly(vinylpyrrolidone), PVP, from anionic silica surfaces by sodium dodecyl sulfate, SDS, was observed. While photon correlation spectroscopy shows that the size of the polymer-surfactant-particle ensemble grows with added SDS, a reduction in the near-surface polymer concentration is measured by solvent relaxation NMR. Volume fraction profiles of the polymer layer extracted from small-angle neutron scattering experiments illustrate that the adsorbed polymer layer has become more diffuse and the polymer chains more elongated as a result of the addition of SDS. The total adsorbed amount is shown to decrease due to Coulombic repulsion between the surfactant-polymer complexes and between the complexes and the anionic silica surface.
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Affiliation(s)
- Beatrice Cattoz
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK
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20
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Fang Y, Ren Y, Jiang M. Co-effect of soft template and microwave irradiation on morphological control of gold nanobranches. Colloid Polym Sci 2011. [DOI: 10.1007/s00396-011-2493-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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21
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Mukherjee I, Sarkar D, Moulik SP. Interaction of gums (guar, carboxymethylhydroxypropyl guar, diutan, and xanthan) with surfactants (DTAB, CTAB, and TX-100) in aqueous medium. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:17906-17912. [PMID: 21033684 DOI: 10.1021/la102717v] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The interaction of surfactants dodecyltrimethylammonium bromide (DTAB), cetyltrimethylammonium bromide (CTAB), and p-tert-octylphenoxypolyoxyethylene (9.5) ether (TX-100) with guar (Gr), carboxymethylhydroxypropyl guar (CMHPG), diutan (Dn), and xanthan (Xn) gums has been studied employing conductometry, tensiometry, microcalorimetry, viscometry, and atomic force microscopy (AFM) techniques. Both weak and strong interactions were observed. CTAB interacted stronger than DTAB with the gums. The surfactant-gum interaction process was enhanced by the presence of borate ions in the solution; the borate ion itself also manifested interaction with the surfactants comparable with that of water-soluble polymers polyvinyl alcohol, polyoxyethylene, and so forth. Viscometric results supported configurational changes of the gum molecules by interaction with surfactants. The geometry of the pure gums and their CTAB interacted products in the dried states was ascertained from AFM measurements; spherical and prolate shapes were observed for pure gums, and distorted states were observed for their surfactant complexed species. Detailed topological features of these entities were ascertained.
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Affiliation(s)
- Indrajyoti Mukherjee
- Center for Surface Science, Department of Chemistry, Jadavpur University, Kolkata 700032, India
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Pojják K, Mészáros R. Novel self-assemblies of oppositely charged polyelectrolytes and surfactants in the presence of neutral polymer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:13336-13339. [PMID: 19874012 DOI: 10.1021/la903761r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this Letter, the effect of addition of poly(ethylene oxide) (PEO) on the nature of the self-assemblies of sodium dodecyl sulfate (SDS) and branched poly(ethyleneimine) (PEI) is investigated. We demonstrate that the neutral polymer adsorbs onto the surface of the polyelectrolyte/surfactant nanoparticles, which may result in sterically stabilized colloidal dispersions of the nanoparticles with hydrophobic core and hydrophilic corona. The kinetic stability is maintained even at high ionic strengths, where the charge stabilization of the PEI/SDS dispersions is inefficient. These results might be exploited to improve the efficiency of those formulations, which contain oppositely charged macromolecules and amphiphiles.
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Affiliation(s)
- Katalin Pojják
- Laboratory of Interfaces and Nanosized Systems, Institute of Chemistry, Eotvos Lorand University, 1117 Budapest, Pazmany Peter setany 1/A, Hungary
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Nedjhioui M, Moulai-Mostefa N, Canselier JP, Bensmaili A. Investigation of Combined Effects of Xanthan Gum, Sodium Dodecyl Sulphate, and Salt on Some Physicochemical Properties of Their Mixtures Using a Response Surface Method. J DISPER SCI TECHNOL 2009. [DOI: 10.1080/01932690902735538] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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25
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de Vos WM, Biesheuvel PM, de Keizer A, Kleijn JM, Cohen Stuart MA. Adsorption of anionic surfactants in a nonionic polymer brush: experiments, comparison with mean-field theory, and implications for brush-particle interaction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:9252-61. [PMID: 19719223 DOI: 10.1021/la900791b] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The adsorption of the anionic surfactants sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfonate (SDBS) in poly(ethylene oxide) (PEO) brushes was studied using a fixed-angle optical flow-cell reflectometer. We show that, just as in solution, there is a critical association concentration (CAC) for the surfactants at which adsorption in the PEO brush starts. Above the critical micelle concentration (CMC) the adsorption is found to be completely reversible. At low brush density the adsorption per PEO monomer is equal to the adsorption of these surfactants in bulk solution. However, with increasing brush density, the number of adsorbed surfactant molecules per PEO monomer decreases rapidly. This decrease is explained in terms of excluded volume interactions plus electrostatic repulsion between the negatively charged surfactant micelles. Experimentally, a plateau value in the total adsorption is observed as a function of grafting density. The experimental results were compared to the results of an analytical self-consistent field (aSCF) model, and we found quantitative agreement. Additionally, the model predicts that the plateau value found is in fact a maximum. Both experiments and model calculations show that the adsorption scales directly with the polymerization degree of the polymers in the brush. They also show that an increase in the ionic strength leads to an increase in the adsorbed amount, which is explained as being due to a decrease in the electrostatic penalty for the adsorption of the SDS micelles. The adsorption of SDS micelles changes the interactions of the PEO brush with a silica particle. This is illustrated by atomic force microscopy (AFM) measurements of the pull-off force of a silica particle from a PEO brush: at high enough PEO densities, the addition of SDS leads to a very strong reduction in the force necessary to detach the colloidal silica particle from the PEO brush. We attribute this effect to the large amount of negative charge incorporated in the PEO brush due to SDS adsorption.
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Affiliation(s)
- Wiebe M de Vos
- Laboratory of Physical Chemistry and Colloid Science, Department of Environmental Technology, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands
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Balmer JA, Armes SP, Fowler PW, Tarnai T, Gáspár Z, Murray KA, Williams NSJ. Packing efficiency of small silica particles on large latex particles: a facile route to colloidal nanocomposites. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:5339-47. [PMID: 19260684 DOI: 10.1021/la8041555] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The adsorption of small silica particles onto large sterically stabilized poly(2-vinylpyridine) [P2VP] latex particles in aqueous solution is assessed as a potential route to nanocomposite particles with a "core-shell" morphology. Geometric considerations allow the packing efficiency, P, to be related to the number of adsorbed silica particles per latex particle, N. Making no assumptions about the packing structure, this approach leads to a theoretical estimate for P of 86 +/- 4%. Experimentally, dynamic light scattering is used to obtain a plot of hydrodynamic diameter against N, which indicates the conditions required for monolayer coverage of the latex by the silica particles. Transmission electron microscopy confirmed that, at approximately monolayer coverage, calcination of these nanocomposite particles led to the formation of well-defined hollow silica shells. This is interpreted as strong evidence for a contiguous monolayer of silica particles surrounding the latex cores. On this basis, an experimental value for P of 69 +/- 4% was estimated for nanocomposite particles prepared by the heteroflocculation of a 20 nm silica sol with near-monodisperse P2VP latexes of either 463 or 616 nm diameter at approximately pH 10. X-ray photoelectron spectroscopy was used to quantify the extent of latex surface coverage by the silica particles. This technique gave good agreement with the silica packing efficiencies estimated from calcination studies.
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Affiliation(s)
- Jennifer A Balmer
- Dainton Building, Department of Chemistry, The University of Sheffield, Sheffield, Brook Hill, S3 7HF United Kingdom
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27
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Govender S, Swart P. Surfactant formulations for multi-functional surface modification. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2008.07.057] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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28
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Joseph J, Dreiss CA, Cosgrove T. Stretching a polymer brush by making in situ cyclodextrin inclusion complexes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:10005-10. [PMID: 18712892 DOI: 10.1021/la801088q] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The interaction between poly(ethylene oxide) (PEO) chains grafted onto polystyrene latex particles and alpha-, beta-, and gamma-cyclodextrins (CD) was studied by small-angle neutron scattering. The particles were contrast-matched to the solvent in order that only the scattering from the polymer layers was detected. The signal from the layers was fitted to a double-exponential volume fraction profile. The effects of adding cyclodextrin on the polymer profile are shown as a function of cyclodextrin concentration. The polymer layers are seen to extend on addition of CD, which is consistent with a complexation between the grafted PEO and the CD molecules. The effect is the strongest with alpha-CD.
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Affiliation(s)
- Julie Joseph
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, U.K
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29
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Flood C, Cosgrove T, Espidel Y, Welfare E, Howell I, Revell P. Fourier-transform Carr-Purcell-Meiboom-Gill NMR experiments on polymers in colloidal dispersions: how many polymer molecules per particle? LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7875-7880. [PMID: 18588323 DOI: 10.1021/la800144c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Fourier transform relaxation NMR has been used to study how the mobility of poly(ethylene oxide) is affected by its adsorption onto colloidal silica particles of various sizes. Novel results have been obtained which illustrate the unexploited potential of this method for the study of interfacial species in complex systems. The results quantify how polymer mobility varies along an adsorption isotherm. When the particles are in excess, the polymer is strongly adsorbed and hence has a large spin-spin magnetic relaxation rate constant, R(2). The value of R(2) in this region increases with particle size, because the associated reduction in particle surface curvature results in a reduction in the mobility of the adsorbed polymer. This is accompanied by a reduction in the signal intensity, as a higher fraction of the polymer is adsorbed in the form of train segments too immobile to detect using the Carr-Purcell-Meiboom-Gill pulse sequence. When the polymer concentration reaches approximately 0.5 mg m(-2), the initial region of high affinity adsorption ends and so the polymer solution concentration increases. This is accompanied by a reduction in R(2), which then approaches the value for a simple polymer solution in the absence of particles. The results are corroborated by comparison with rheological measurements and molecular dynamics simulations of an analogous particle-polymer system.
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Affiliation(s)
- Charlie Flood
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
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Flood C, Cosgrove T, Espidel Y, Howell I, Revell P. Effects of surfactants and electrolytes on adsorbed layers and particle stability. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:7323-7328. [PMID: 18547088 DOI: 10.1021/la800143x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Adsorbed polymer and polyelectrolyte layers on colloidal silica nanoparticles have been studied in the presence of various salts and surfactants using photon correlation spectroscopy and solvent relaxation NMR. Poly(ethylene oxide) (PEO; molar mass 103.6 kg mol (-1)) adsorbed with a relatively high affinity and gave a layer thickness of 4.2 +/- 0.2 nm. While the nonionic surfactant used only increased this thickness slightly, anionic surfactants had a much greater effect, mainly due to repulsions between adsorbed aggregates, leading to expansion of the layer. A nonionic/anionic surfactant mixture was also tested and resulted in a larger increase in layer thickness than any of the individual surfactants. The dominant factor on addition of salt was generally the reduced solvency of PEO, which resulted in a further increase in the layer thickness but in some cases caused flocculation. This was not the case when the surfactant was sodium dodecylbenzenesulfonate; instead screening of the intermicellar repulsions possibly combined with surfactant-cation binding resulted in a reduction in the layer thickness. In comparison the affinity between silica and sodium polystyrenesulfonate was very weak. Anionic surfactants and salts did not noticeably increase the strength of adsorption, but instead encouraged flocculation. The situation was different with a nonionic surfactant, which was able to adsorb to silica itself and apparently facilitated a degree of polyelectrolyte adsorption as well.
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Affiliation(s)
- Charlie Flood
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
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31
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Naderi A, Makuška R, Claesson PM. Interactions between bottle-brush polyelectrolyte layers: Effects of ionic strength and oppositely charged surfactant. J Colloid Interface Sci 2008; 323:191-202. [DOI: 10.1016/j.jcis.2008.02.071] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Revised: 02/26/2008] [Accepted: 02/26/2008] [Indexed: 10/22/2022]
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32
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Osmotic pressure and chemical potential of silica nanoparticles in aqueous poly(ethyleneoxide) solution. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2007.10.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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33
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Sepassi S, Goodwin DJ, Drake AF, Holland S, Leonard G, Martini L, Lawrence MJ. Effect of polymer molecular weight on the production of drug nanoparticles. J Pharm Sci 2007; 96:2655-66. [PMID: 17696165 DOI: 10.1002/jps.20979] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Stable, polymer-coated nanoparticles of two hydrophobic drugs, namely nabumetone and halofantrine, have been prepared by a wet-bead milling process performed in the presence of a stabilizing homopolymer, either hydroxypropylmethylcellulose (HPMC) or polyvinylpyrrolidone (PVP), of differing molecular weights and concentrations. Although nabumetone nanoparticles could only be produced when HPMC was used as stabilizing polymer, halofantrine nanoparticles could be prepared using either HPMC or PVP. Stable nanoparticles of nabumetone could be produced using a HPMC solution of viscosity average molecular weight, M(v), of 5 kg/mol over an approximate four fold polymer concentration range (0.63-2.5% w/w) when a drug loading of 20% w/w was used. Increasing the molecular weight of HPMC up to a limiting M(v) of 89 kg/mol did not result in the formation of nanoparticles at any of the polymer concentrations examined. The amount of polymer absorbed onto the nanoparticles was determined by measuring the depletion of polymer from solution based on either an ultra-violet (PVP) or optical rotatory dispersion (ORD) (HPMC) assay. The slightly lower concentration of HMPC found to be present on the surface of the halofantrine nanoparticles compared with the nabumetone nanoparticles suggested a differing affinity of the polymer for the surface of the two drugs.
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Affiliation(s)
- S Sepassi
- Department of Pharmacy, King's College London, 150 Stamford Street, London SE1 9NH, United Kingdom
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34
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Govender S, Jacobs EP, Bredenkamp MW, Swart P. Affinity chromatography using biocompatible and reusable biotinylated membranes. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 859:1-8. [PMID: 17875407 DOI: 10.1016/j.jchromb.2007.08.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Revised: 08/15/2007] [Accepted: 08/21/2007] [Indexed: 10/22/2022]
Abstract
A novel, reusable biotinylated affinity chromatography strategy for the bio-specific binding of bioactive avidin tagged enzymes or polypeptides is reported. Using an avidin coupled peroxidase fusion protein as a test system; non-specific protein shielding and matrix regeneration were also shown. The amphiphilic surfactant Pluronic F108 was used as an affinity linker, by non-covalent binding to membrane chromatographic matrices while the terminal hydroxyl groups of Pluronic were covalently coupled to the biological ligand biotin. Planar nonporous membranes of varying surface chemistry were synthesised to test the matrix dependent affinity binding of biotinylated Pluronic and their respective ability to resist non-specific protein adsorption. Membrane regeneration using sodium dodecyl sulphate (SDS) was capable of displacing both adsorbed proteins and Pluronic. SDS micelles (34 mM) were effective in desorbing membrane bound protein while 5mM SDS removed up to 85% of the bound ligand after 20 h incubation at 20 degrees C. In this study, polyvinylidene membranes had the highest ligand binding capacity of 0.22 mg cm(-2) and specific, competitive affinity binding of avidin-peroxidase was shown in the presence of up to 0.2 mg ml(-1) 'contaminant' proteins. The resultant biocompatible affinity chromatographic system was regenerated and reused with no significant change in performance for up to five cycles.
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Affiliation(s)
- S Govender
- Department of Biochemistry, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
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35
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Boissier C, Löfroth JE, Nydén M. Interactions between polyvinylpyrrolidone, sodium dodecylsulfate and nonylphenol ethoxylate in solution and on polystyrene particles. Colloids Surf A Physicochem Eng Asp 2007. [DOI: 10.1016/j.colsurfa.2007.01.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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36
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Flood C, Cosgrove T, Qiu D, Espidel Y, Howell I, Revell P. Influence of a surfactant and electrolytes on adsorbed polymer layers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:2408-13. [PMID: 17309202 DOI: 10.1021/la062034b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Solvent relaxation NMR and small-angle neutron scattering have been used to characterize adsorbed poly(ethylene oxide) (PEO) layers on silica at a range of surfactant and electrolyte concentrations. Below the critical aggregation concentration (cac), the results suggest that sodium dodecyl sulfate (SDS) interacts relatively weakly, perhaps analogously to a simple salt reducing the solvency of PEO. This is evidenced by a decrease in the adsorbed layer thickness combined with an increase in the bound fraction, although the total adsorbed amount is not greatly affected. The layer thickness goes through a minimum at the cac, after which further SDS addition results in the formation of PEO/SDS aggregates that repel each other and, hence, tend to desorb. The adsorbed amount therefore decreases, from 0.7 mg m(-2) initially to 0.2 mg m(-2) with 32 mM SDS. The aggregates that remain adsorbed also repel, and hence, there is an increase in the layer thickness and the persistence length, while the bound fraction is reduced. In comparison, the effects of electrolyte at the ionic strength studied are relatively minimal. There is, however, evidence that the repulsions between adsorbed PEO/SDS aggregates are partially screened, allowing them to approach each other more readily. This leads to a contraction of the adsorbed layer when the SDS concentration is sufficiently high.
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Affiliation(s)
- Charlie Flood
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.
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37
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Alava C, Saunders BR. Polymer stabilisers for temperature-induced dispersion gelation: Versatility and control. J Colloid Interface Sci 2006; 293:93-100. [PMID: 16023128 DOI: 10.1016/j.jcis.2005.06.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 06/03/2005] [Accepted: 06/09/2005] [Indexed: 11/16/2022]
Abstract
In this study the temperature-induced gelation of butadiene-acrylonitrile latex containing the added temperature-responsive polymer surfactant, poly(NIPAM-co-PEGMa) is investigated for the first time. (NIPAM and PEGMa are N-isopropylacrylamide and poly(ethylene glycol)methacrylate, respectively.) The results are compared with temperature-induced gelation of oil-in-water emulsions containing 1-bromohexadecane. The effect of added anionic surfactant, NaDBS (sodium dodecylbenzene sulfonate) on the temperature-induced gelation process and mechanism is considered. It was found that the gelation temperature (T(gel)) for the latex occurs at the cloud point temperature (T(cpt)) of the polymer and that T(gel) is much less affected by added NaDBS than is the case for emulsion gelation. The mathematical predictive theory recently derived for temperature-induced emulsion gelation was applied to the latex data and gave a good fit (i.e., T(gel) approximately 1/C(p), where C(p) is the concentration of added poly(NIPAM-co-PEGMa)). However, the causes for the variation of T(gel) with C(p) for temperature-induced latex and emulsion gelation are different. The variation of T(gel) for latex gelation in the presence of added NaDBS originates from surfactant association with poly(NIPAM-co-PEGMa) which increased T(cpt). In the case of emulsion gelation there are electrostatic interactions above T(cpt) which control T(gel). The subtle difference in the temperature-induced latex gelation mechanism is a consequence of the very high latex surface area (cf. emulsion), small inter-particle separation and the presence of electrolyte. The reason that T(gel) follows 1/C(p) for the latex is due to a fortuitous T(cpt) approximately 1/C(p) relationship that applies for poly(NIPAM-co-PEGMa) solution in the presence of NaDBS. The work presented here shows that addition of poly(NIPAM-co-PEGMa) to dispersions gives a versatile method for temperature-triggered gelation. Furthermore, the theory presented provides a framework for predicting their gelation temperatures.
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Affiliation(s)
- Cristina Alava
- School of Materials, The University of Manchester, Grosvenor Street, Manchester M1 7HS, UK
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38
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Vangeyte P, Leyh B, De Clercq C, Auvray L, Misselyn-Bauduin AM, Jérôme R. Concomitant adsorption of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers and sodium dodecyl sulfate at the silica-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:7710-6. [PMID: 16089373 DOI: 10.1021/la047051k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Upon addition of silica to aqueous solutions of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers (PEO-b-PCL) and sodium dodecyl sulfate (SDS), adsorption of the solutes occurs at the silica-water interface. The amount of the adsorbed constituents has been measured by the total concentration depletion method. Small-angle neutron scattering experiments (SANS) have been carried out to investigate the structure of the adsorbed layer. Although SDS is not spontaneously adsorbed onto hydrophilic silica, adsorption is observed in the presence of PEO-b-PCL diblocks, in relation to the relative concentration of the two compounds. Conversely, SDS has a depressive effect on the adsorption of the copolymer, whose structure at the interface is modified. Copolymer desorption is however never complete at high SDS content. These observations have been rationalized by the associative behavior of PEO-b-PCL and SDS in water.
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Affiliation(s)
- P Vangeyte
- Center for Education and Research on Macromolecules, University of Liège, Sart-Tilman B6a, B-4000 Liège, Belgium
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39
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Studies on the interaction between tetradecyl dimethyl betaine and sodium carboxymethyl cellulose by DPD simulations. Colloids Surf A Physicochem Eng Asp 2005. [DOI: 10.1016/j.colsurfa.2004.10.120] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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40
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Olsson M, Boström G, Karlson L, Piculell L. Added surfactant can change the phase behavior of aqueous polymer-particle mixtures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:2743-2749. [PMID: 15779943 DOI: 10.1021/la0473254] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The phase behavior of aqueous mixtures of the "clouding" polymer ethyl(hydroxyethyl)cellulose (EHEC) mixed with colloidal particles and surfactants has been studied. These types of mixtures are important in many technical formulations. Two types of particles, polystyrene latex and silica, and two types of EHEC, nonmodified EHEC (N-EHEC) and hydrophobically modified EHEC (HM-EHEC), were studied. The EHECs adsorb to both kinds of particles. Both the amount and the type of added surfactant were seen to dramatically influence the partitioning of the particles between the EHEC-rich and EHEC-poor phases of phase-separated mixtures (above the cloud point temperature). Surfactants that are known not to associate with the EHEC backbone, that is, nonionic surfactants and short-chain cationic surfactants, changed the interaction between EHEC and the colloidal particles from attraction to repulsion above a specific surfactant concentration, resulting in a change in the partitioning of the particles from the EHEC-rich to the EHEC-poor phase. No such particle inversion was observed for ionic surfactants that bind to the EHEC backbone. An analysis considering both the binding of surfactant to EHEC and the competitive adsorption of surfactant to the particle surfaces could rationalize all observations, including the large variations observed, among the studied mixtures, in the surfactant concentration required for particle inversion.
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Affiliation(s)
- Martin Olsson
- Division of Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
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41
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Prestidge CA, Barnes T, Simovic S. Polymer and particle adsorption at the PDMS droplet-water interface. Adv Colloid Interface Sci 2004; 108-109:105-18. [PMID: 15072933 DOI: 10.1016/j.cis.2003.10.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Polymer and particle adsorption at the polydimethylsiloxane (PDMS) droplet-water interface has been investigated. Adsorption isotherms and adsorbed layer structure are reported for a range of PEO-PPO-PEO block copolymers, and hydrophilic and hydrophobic silica "nanoparticles". The influence of solution conditions on the adsorption behaviour has indicated the thermodynamics of polymer-droplet and particle-droplet interactions. The influence of droplet cross-linking (deformability) has indicated the role of interfacial penetration in controlling adsorption at the droplet-water interface. The plateau adsorbed amount (Gamma(max)) and adsorbed layer thickness (delta(max)) of PEO-PPO-PEO copolymers are dependent on the copolymer structure and the level of cross-linking within droplets. For a wide range of copolymer structures, Gamma(max) values are in the range 2 to 20 mg m(-2). For delta(max), values range from 2 to 20 nm and are directly proportional to the PEO block length. Droplet cross-linking significantly reduces Gamma and delta values; this is considered to be due to the influence of interfacial penetrability on the adsorbed copolymer conformation. Hydrophilic silica particles adsorb onto PDMS droplets with plateau surface coverages that correspond to their hard sphere radius+double layer thickness, i.e. lateral silica-silica interactions control particle packing. Free energies of adsorption (DeltaG(ads)) are concurrent with a physical adsorption mechanism. Surface coverages, DeltaG(ads) and particle packing at the interface are only weakly influenced by pH, but are significantly influenced by salt addition. Droplet cross-linking reduced particle adsorption only at higher salt concentrations; this was attributed to the increased likelihood of silica particles wetting PDMS. Freeze fracture SEM revealed that individual silica particles are adsorbed at the droplet interface with negligible interfacial aggregation. Densely packed adsorbed particle layers are only observed when the double layer thickness is a few nanometers. Adsorption of hydrophobic particles at the PDMS droplet-water interface is more pronounced (greater adsorbed amounts and DeltaG(ads) values) than for hydrophilic particles and displays a pH dependency in line with 'DLVO behaviour'. The surface coverage values correspond to multiple close packed layers and are significantly influenced by droplet cross-linking, conferring extensive interfacial penetration (confirmed by SEM). Densely packed adsorbed particle layers with interfacial aggregation are observed over a wide range of solution conditions. Interfacial particle saturation occurred at a salt concentration two orders of magnitude less than the critical coagulation concentration (ccc) for silica in water. This phenomenon was observed for both liquid and cross-linked PDMS droplets indicating that particle interaction through the water phase plays a decisive role in particle packing at the interface. SEM indicated the presence of a rigid interfacial crust layer at the salt concentration corresponding to interfacial saturation and a multi-layered interfacial particle wall at salt concentrations >/= ccc. The PDMS droplets under consideration, having inherent colloid stability in the absence of added stabilisers, are an excellent model system for characterising polymer and particle adsorption at the droplet-water interface. The insight gained concerning adsorption thermodynamics at the droplet-water interface is not available from more conventional emulsions.
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Affiliation(s)
- Clive A Prestidge
- Ian Wark Research Institute, The ARC Special Research Centre for Particle and Material Interfaces, University of South Australia, Mawson Lakes, SA 5095, Australia.
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42
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Alava C, Saunders BR. Effect of added surfactant on temperature-induced gelation of emulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:3107-13. [PMID: 15875836 DOI: 10.1021/la036371l] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
This paper involves an investigation of the effect of added ionic surfactant on the temperature-induced gelation of oil-in-water (O/W) emulsions stabilized by a responsive copolymer. The oil phase used in this study is 1-bromohexadecane. The copolymer is poly(NIPAM-co-PEGMa) (NIPAM and PEGMa are N-isopropylacrylamide and poly(ethylene glycol) methacrylate, respectively). The lower critical solution temperature for the copolymer was 39.5 degrees C. The ionic surfactant used in this work was sodium dodecylbenzenesulfonate (NaDBS). The critical association concentration for NaDBS and poly(NIPAM-co-PEGMa) was measured at 0.30 mM using fluorescence measurements (pyrene was the probe molecule). Gelation temperatures were measured for the O/W emulsions to establish the effect of added NaDBS and copolymer concentration (Cp) on the gelation temperature (Tgel). The strength of the gels was measured using dynamic oscillatory measurements. These measurements allowed the shear modulus of the gel at Tgel to be estimated as 100 Pa. A theoretical model based on transient network theory was developed that predicts the dependence of Tgel on Cp. The study revealed that NaDBS has two effects on the overall cross-link density of the emulsion gels: it contributes a source of cross-linking via micellar cross-links and also decreases the proportion of transient cross-links due to electrostatic repulsion.
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Affiliation(s)
- Cristina Alava
- Manchester Materials Science Centre, UMIST and the University of Manchester, Manchester M1 7HS, UK
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43
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Zimin D, Craig VSJ, Kunz W. Adsorption pattern of mixtures of trimethylammonium-modified hydroxyethylcellulose and sodium dodecyl sulfate at solid-liquid interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:2282-2291. [PMID: 15835685 DOI: 10.1021/la035112t] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We studied mixtures of aqueous solutions of cationic hydroxyethylcellulose JR400 polymer and anionic sodium dodecyl sulfate using dynamic light scattering and atomic force microscopy (AFM). A ternary phase diagram was established showing three interesting realms of the polymer-surfactant-water mixture: a preprecipitation area of lowered viscosity (polymer excess) compared to the pure polymer solution, a postprecipitation area (resolubilization at surfactant excess), and highly diluted samples with a stoichiometrical surfactant-polymer ratio close to that of maximum precipitation. Samples with various compositions representing these areas were imaged by atomic force microscopy on mica and on hydrophobically modified silica in contact mode. A correlation between light scattering data concerning particle size and, more important, structuring in the bulk on one hand and AFM images on the other hand was observed. It was revealed that the influence of surface properties is of less importance for adsorption, compared to the influence of the mixture in the bulk, provided that the mixture is prepared prior to adsorption.
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Affiliation(s)
- D Zimin
- Institute of Physical and Theoretical Chemistry, University of Regensburg, D-93040 Regensburg, Germany
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Notley SM, Biggs S, Craig VSJ, Wågberg L. Adsorbed layer structure of a weak polyelectrolyte studied by colloidal probe microscopy and QCM-D as a function of pH and ionic strength. Phys Chem Chem Phys 2004. [DOI: 10.1039/b401376j] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Partitioning behavior of silica in the PEG/dextran/H2O aqueous biphasic system. Colloids Surf A Physicochem Eng Asp 2003. [DOI: 10.1016/s0927-7757(03)00354-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Mubarekyan E, Santore MM. Energy Barrier to Self-Exchange between PEO Adsorbed on Silica and in Solution. Macromolecules 2001. [DOI: 10.1021/ma010132s] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ervin Mubarekyan
- Department of Chemical Engineering, Lehigh University, 111 Research Drive, Bethlehem, Pennsylvania 18015
| | - Maria M. Santore
- Department of Chemical Engineering, Lehigh University, 111 Research Drive, Bethlehem, Pennsylvania 18015
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Sadowski Z, Polowczyk I. Effect of Polymer–Surfactant Adsorption on the Hindered Settling of a Mineral Suspension. ADSORPT SCI TECHNOL 2001. [DOI: 10.1260/0263617011494132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Competitive adsorption between anionic surfactant (SDS) and neutral poly(ethylene oxide) polymers (PEO) on carbonate mine tailings was investigated, with experiments being performed to check the order of reagent addition. The PEO adsorption plateaux were strongly affected by the presence of pre-adsorbed surfactant molecules, while surfactant adsorption increased in the presence of pre-adsorbed polymer. Polymer–surfactant interaction at the solid–liquid interface depended on the order of reagent addition which significantly affected the floc diameter. Increasing floc diameter was attributed to the formation of a polymer–surfactant complex on the solid surface.
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Affiliation(s)
- Zygmunt Sadowski
- Department of Chemical Engineering & Heating Equipment, Faculty of Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
| | - Izabela Polowczyk
- Department of Chemical Engineering & Heating Equipment, Faculty of Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
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