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Xiong Y, Peng K, Zhao Z, Yang D, Huang X, Zeng H. Sources, colloidal characteristics, and separation technologies for highly hazardous waste nanoemulsions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 930:172347. [PMID: 38614332 DOI: 10.1016/j.scitotenv.2024.172347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 03/27/2024] [Accepted: 04/08/2024] [Indexed: 04/15/2024]
Abstract
Nanoemulsions play a crucial role in various industries. However, their application often results in hazardous waste, posing significant risks to human health and the environment. Effective management and separation of waste nanoemulsions requires special attention and effort. This review provides a comprehensive understanding of waste nanoemulsions, covering their sources, characteristics, and suitable treatment technologies, intending to mitigate their environmental impact. This study examines the evolution of nanoemulsions from beneficial products to hazardous wastes, provides an overview of the production processes, fate, and hazards of waste nanoemulsions, and highlights the critical characteristics that affect their stability. The latest advancements in separating waste nanoemulsions for recovering oil and reusable water resources are also presented, providing a comprehensive comparison and evaluation of the current treatment techniques. This review addresses the significant challenges in nanoemulsion treatment, provides insights into future research directions, and offers valuable implications for the development of more effective strategies to mitigate the hazards associated with waste nanoemulsions.
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Affiliation(s)
- Yongjiao Xiong
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092, PR China
| | - Kaiming Peng
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092, PR China; Institute of Carbon Neutrality, Tongji University, No. 1239 Siping Road, Shanghai 200092, PR China
| | - Ziqian Zhao
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Diling Yang
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Xiangfeng Huang
- State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, No. 1239 Siping Road, Shanghai 200092, PR China; Institute of Carbon Neutrality, Tongji University, No. 1239 Siping Road, Shanghai 200092, PR China.
| | - Hongbo Zeng
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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Kumar H, Tiwari M, Dugyala VR, Basavaraj MG. Single-Step Formation of Pickering Double Emulsions by Exploiting Differential Wettability of Particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7860-7870. [PMID: 38557075 DOI: 10.1021/acs.langmuir.3c03374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
We present a modular single-step strategy for the formation of single and Pickering double emulsions (DEs). To this end, we consider the role of surface modification of particles and their dispersibility in different phases in the context of the design of Pickering emulsions by varying the volume fraction of oil in the oil-water mixture (ϕoil) used for emulsification. In particular, the experiments are performed by considering (a) model spherical and nonspherical colloids of different wettabilities which are tailored by oleic acid treatment, (b) immiscible liquids with or without particles, and (c) varying ϕoil from 0.1 to 0.9. We show that it is possible to affect a transition from (i) oil-in-water (O/W) emulsion to water-in-oil (W/O) emulsion and (ii) oil-in-water (O/W) to oil-in-water-in-oil (O/W/O) to water-in-oil (W/O) as ϕoil is systematically varied. We elucidate that the range of ϕoil at which particle stabilized DEs of the O/W/O type form can be tuned by engineering surface modification of particles to different extents. Furthermore, the arrangement of particles on the surface of droplets in the Pickering DEs is discussed. Our results conclusively establish that the differential wettability of particles is the key for the design of Pickering DEs. The versatility of the proposed strategy is established by developing DEs using a number of model colloidal systems.
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Affiliation(s)
- Hemant Kumar
- Polymer Engineering and Colloid Science (PECS) Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India
| | - Madhvi Tiwari
- Department of Chemical Engineering, Indian Institute of Science Education and Research Bhopal, Bhopal, Madhya Pradesh 462066, India
| | - Venkateshwar Rao Dugyala
- Department of Chemical Engineering, Indian Institute of Science Education and Research Bhopal, Bhopal, Madhya Pradesh 462066, India
| | - Madivala G Basavaraj
- Polymer Engineering and Colloid Science (PECS) Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India
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Conformational evolution of soybean protein-polysaccharide at oil-water interface in simulated gastric environment in vitro. Food Chem 2023; 413:135613. [PMID: 36758390 DOI: 10.1016/j.foodchem.2023.135613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/29/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023]
Abstract
The conformation and characteristics of soybean hull polysaccharide (SHP)/soy bean protein isolate (SPI) complex at oil-water interface in simulated gastric environment in vitro were discussed. Isothermal titration calorimetry (ITC) thermodynamic results illustrated that SPI formed a complex with SHP. ζ-potential and microstructure showed a flocculation phenomenon after SPI/SHP emulsion droplet treatment (especially at 60 min), which indicated that the inter droplet steric hindrance and repulsion were reduced after the emulsion was treated. Additionally, at 60 min, in FT-IR spectrum fitting results, the contents of β-sheet and β-turn structure were the lowest, which might be that the polar group residues exposed in the SPI/SHP complex at the interface interacted with Na+ by ion-dipole interaction or protonated with H+. The blue shift of maximum absorption intensity also indicated that the tryptophan residues moved to the hydrophobic environment, which made the treated droplets flocculate without obvious aggregation.
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Yang C, Li J, Zhang Y, Wu C, Li D. A pesticide sustained‐release microcapsule from cellulose nanocrystal stabilized Pickering emulsion template. J Appl Polym Sci 2023. [DOI: 10.1002/app.53716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Cai‐xia Yang
- Xinjiang Key Laboratory of Agricultural Chemistry and Biomaterials, College of Chemistry and Chemical Engineering Xinjiang Agricultural University Urumchi People's Republic of China
| | - Jun Li
- Xinjiang Key Laboratory of Agricultural Chemistry and Biomaterials, College of Chemistry and Chemical Engineering Xinjiang Agricultural University Urumchi People's Republic of China
| | - Yu‐qing Zhang
- Xinjiang Key Laboratory of Agricultural Chemistry and Biomaterials, College of Chemistry and Chemical Engineering Xinjiang Agricultural University Urumchi People's Republic of China
| | - Chao Wu
- Xinjiang Key Laboratory of Agricultural Chemistry and Biomaterials, College of Chemistry and Chemical Engineering Xinjiang Agricultural University Urumchi People's Republic of China
| | - De‐qiang Li
- Xinjiang Key Laboratory of Agricultural Chemistry and Biomaterials, College of Chemistry and Chemical Engineering Xinjiang Agricultural University Urumchi People's Republic of China
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Sun G, Guo T, Luo J, Liu R, Ngai T, Binks BP. Phase Inversion of Pickering Emulsions Induced by Interfacial Electrostatic Attraction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:1386-1393. [PMID: 36633936 DOI: 10.1021/acs.langmuir.2c02048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Phase inversion of Pickering emulsions from water-in-oil (W/O) to oil-in-water (O/W) is achieved by the formation of an interfacial particle bilayer using negatively charged and positively charged particles dispersed in water and oil, respectively, before emulsification. A mechanism based on electrostatic attraction across the toluene-water interface is proposed and verified by systematic investigation of the parameters that affect the surface charge of negatively charged particles such as pH and salt concentration. Cationic silica-FITC particles (600 nm) can be dispersed in toluene and stabilize W/O emulsions alone; phase inversion of this emulsion can be induced by the addition of anionic silica-RB particles in the aqueous phase at a concentration of 1.0 wt % or above. It is revealed that silica-RB particles of a smaller size (100 nm) can induce emulsion phase inversion at a much lower concentration (0.4 wt %) and an interfacial particle bilayer is clearly revealed by CLSM and SEM images. By tuning the surface charge density of silica-RB particles, the electrostatic attraction mechanism leading to the formation of the interfacial particle bilayer is confirmed and emulsion stability can be tuned as demonstrated by osmotic pressure enhancement results obtained from centrifugation.
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Affiliation(s)
- Guanqing Sun
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Tiehuang Guo
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Jing Luo
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Ren Liu
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - To Ngai
- Department of Chemistry, The Chinese University of Hong Kong, Shatin 000000, N.T. Hong Kong, China
| | - Bernard P Binks
- Department of Chemistry, University of Hull, Hull HU6 7RX, U.K
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Pickering Emulsions Stabilized by Chitosan/Natural Acacia Gum Biopolymers: Effects of pH and Salt Concentrations. Polymers (Basel) 2022; 14:polym14235270. [PMID: 36501665 PMCID: PMC9738950 DOI: 10.3390/polym14235270] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 11/24/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
In this study, chitosan (CT) and naturally occurring acacia gum (AG) blends were employed as emulsifiers to form a series of emulsions developed from diesel and water. Effects of pH level (3, 5, 10, and 12) and various NaCl salt concentrations (0.25-1%) on the stability, viscosity, and interfacial properties of CT-(1%)/AG-(4%) stabilized Pickering emulsions were evaluated. Bottle test experiment results showed that the stability indexes of the CT/AG emulsions were similar under acidic (3 and 5) and alkaline (10 and 12) pH media. On the other hand, the effects of various NaCl concentrations on the stability of CT-(1%)/AG-(4%) emulsion demonstrated analogous behavior throughout. From all the NaCl concentrations and pH levels examined, viscosities of this emulsion decreased drastically with the increasing shear rate, indicating pseudoplastic fluid with shear thinning characteristics of these emulsions. The viscosity of CT-(1%)/AG-(4%) emulsion increased at a low shear rate and decreased with an increasing shear rate. The presence of NaCl salt and pH change in CT/AG solutions induced a transformation in the interfacial tension (IFT) at the diesel/water interface. Accordingly, the IFT values of diesel/water in the absence of NaCl/CT/AG (without emulsifier and salt) remained fairly constant for a period of 500 s, and its average IFT value was 26.16 mN/m. In the absence of salt, the addition of an emulsifier (CT-(1%)/AG-(4%)) reduced the IFT to 16.69 mN/m. When the salt was added, the IFT values were further reduced to 12.04 mN/m. At low pH, the IFT was higher (17.1 mN/M) compared to the value of the IFT (10.8 mN/M) at high pH. The results obtained will help understand the preparation and performance of such emulsions under different conditions especially relevant to oil field applications.
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pH/Temperature-Responsive Salt-Tolerant Pickering Emulsion Formed by PNIPAM-Modified Chitosan Particles. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Wang S, Gao W, Wang Y, Song T, Qi H, Xiang Z. Emulsifying properties of naturally acetylated xylans and their application in lutein delivery emulsion. Carbohydr Polym 2022; 296:119927. [DOI: 10.1016/j.carbpol.2022.119927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 07/15/2022] [Accepted: 07/25/2022] [Indexed: 11/02/2022]
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Sun S, Deng Y, Sun F, Mao Z, Feng X, Sui X, Liu F, Zhou X, Wang B. Engineering regenerated nanosilk to efficiently stabilize pickering emulsions. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2021.128065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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11
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Zhang Z, Li Q, Sun N, Liu Y, Ge S, Che H, Li A. The preparation of stimulus-responsive Pickering emulsion and its application in preparing microspheres. J DISPER SCI TECHNOL 2022. [DOI: 10.1080/01932691.2021.2025070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Zhaoyu Zhang
- School of Materials Science and Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China
| | - Qiuhong Li
- School of Materials Science and Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China
| | - Ning Sun
- School of Materials Science and Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China
| | - Yunxiao Liu
- Dezhou Linglong Tire Co., Ltd, Dezhou, Shandong, P.R. China
| | - Shujin Ge
- School of Materials Science and Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China
| | - Hongyan Che
- School of Materials Science and Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China
| | - Aixiang Li
- School of Materials Science and Engineering, Shandong University of Technology, Zibo, Shandong, P.R. China
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Haji F, Cheon J, Baek J, Wang Q, Tam KC. Application of Pickering emulsions in probiotic encapsulation- A review. Curr Res Food Sci 2022; 5:1603-1615. [PMID: 36161224 PMCID: PMC9493384 DOI: 10.1016/j.crfs.2022.09.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 09/02/2022] [Accepted: 09/12/2022] [Indexed: 11/25/2022] Open
Abstract
Probiotics are live microorganisms that confer health benefits to host organisms when consumed in adequate amounts and are often incorporated into foods for human consumption. However, this has negative implications on their viability as large numbers of these beneficial bacteria are deactivated when subjected to harsh conditions during processing, storage, and passage through the gastrointestinal tract. To address these issues, numerous studies on encapsulation techniques to protect probiotics have been conducted. This review focuses on emulsion technology for probiotic encapsulation, with a special focus on Pickering emulsions. Pickering emulsions are stabilized by solid particles, which adsorb strongly onto the liquid-liquid interfaces to prevent aggregation. Pickering emulsions have demonstrated enhanced stability, high encapsulation efficiency, and cost-effectiveness compared to other encapsulation techniques. Additionally, Pickering emulsions are regarded as safe and biocompatible and utilize natural materials, such as cellulose and chitosan derived from plants, shellfish, and fungi, which may also be viewed as more acceptable in food systems than common synthetic and natural molecular surfactants. This article reviews the current status of Pickering emulsion use for probiotic delivery and explores the potential of this technique for application in other fields, such as livestock farming, pet food, and aquaculture. Probiotics play an important role in maintaining the health of humans and animals. Encapsulation improves probiotic viability in harsh environments. Probiotics can be encapsulated by many techniques such as emulsification. Pickering emulsions use particles instead of molecules to stabilize emulsions. Natural particles are more acceptable to some consumers than synthetic emulsifiers.
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Affiliation(s)
- Fatemah Haji
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue, Waterloo, ON, N2L 3G1, Canada
| | - James Cheon
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue, Waterloo, ON, N2L 3G1, Canada
| | - Jiyoo Baek
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue, Waterloo, ON, N2L 3G1, Canada
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road W, Guelph, ON, N1G 5C9, Canada
| | - Qi Wang
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road W, Guelph, ON, N1G 5C9, Canada
| | - Kam Chiu Tam
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue, Waterloo, ON, N2L 3G1, Canada
- Corresponding author.
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Bioengineering of neem nano-formulation with adjuvant for better adhesion over applied surface to give long term insect control. Colloids Surf B Biointerfaces 2021; 209:112176. [PMID: 34785423 DOI: 10.1016/j.colsurfb.2021.112176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/24/2021] [Accepted: 10/19/2021] [Indexed: 11/22/2022]
Abstract
Although safe and eco-friendly botanical pesticides have been intensively promoted to combat pest attacks in agriculture, but their stability and efficacies remain an issue for their wide acceptability as sustained and effective approaches. The purpose of this work was to develop stable neem oil based nano-emulsion (NE) formulation with enhanced activity employing suitable bio-inspired adjuvant. So, Neem NEs (with and without) natural adjuvants (Cymbopogon citratus and Prosopis juliflora) in different concentrations were prepared and quality parameters dictating kinetic stability, acidity/alkalinity, viscosity, droplet size, zeta potential, surface tension, stability and compatibility were monitored using Viscometer, Zetasizer, Surface Tensiometer, High Performance Liquid Chromatography (HPLC) and Fourier Transform Infrared Spectroscopy (FTIR). Nano-emulsion biosynthesis optimization studies suggested that slightly acidic (5.9-6.5) NE is kinetically stable with no phase separation; creaming or crystallization may be due to botanical adjuvant (lemongrass oil). Findings proved that Prosopis juliflora, acted as bio-polymeric adjuvant to stabilize NE by increasing Brownian motion and weakening the attractive forces with smaller droplets (25-50 nm), low zeta potential (-30 mV) and poly-dispersive index (<0.3). Botanical adjuvant (30%) based NE with optimum viscosity (98.8cPs) can give long term storage stability and improved adhesiveness and wetting with reduced surface tension and contact angle. FT-IR analysis assured azadirachtin's stability and compatibility with adjuvant. With negligible degradation (1.42%) and higher half-life (t1/2) of 492.95 days, natural adjuvant based NE is substantially stable formulation, may be due to presence of glycosidic and phenolics compounds. Neem 20NE (with 30% adjuvant) exhibited remarkable insecticidal activity (91.24%) against whitefly (Bemisia tabaci G.) in brinjal (Solanum melongena) as evidenced by in-vivo assay. Results thus obtained suggest, bio-pesticide formulation may be used as safer alternative to chemical pesticides to minimize pesticide residues and presence of natural adjuvant may improves the stability and efficacy of biopesticides for safe crop protection in organic agriculture and Integrated Pest Management.
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Tao S, Jiang H, Gong S, Yin S, Li Y, Ngai T. Pickering Emulsions Simultaneously Stabilized by Starch Nanocrystals and Zein Nanoparticles: Fabrication, Characterization, and Application. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:8577-8584. [PMID: 34219459 DOI: 10.1021/acs.langmuir.1c01088] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Using two types of colloidal particles having natural origins to synergistically stabilize Pickering emulsions is essential for food, cosmetics, and pharmaceutics, especially when neither particle can stabilize the Pickering emulsions alone. The use of two natural stabilizers avoids the complicated surface treatments of particles and the introduction of poisonous or harmful chemicals. In this work, we report an all-natural Pickering emulsion stabilized synergistically by starch nanocrystals and zein protein nanoparticles. Our result shows that the electrostatic interaction between the two types of particles greatly affects their assembled structure at the oil/water interface, which is closely related to the emulsion stability. Specifically, particle bilayers could form with oppositely charged particles at the interface to endow the emulsion with improved stability. As a demonstration, the resultant Pickering emulsions effectively carry β-carotene and have high stability against high temperatures and ultraviolet radiation. This type of all-natural Pickering emulsion is a promising tool to protect and deliver liposoluble bioactive components.
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Affiliation(s)
- Shengnan Tao
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Hang Jiang
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Suijing Gong
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Shouwei Yin
- Research and Development Center of Food Proteins, Department of Food Science and Technology, South China University of Technology, Guangzhou 510640, P. R. China
| | - Yunxing Li
- Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - To Ngai
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, N. T., Hong Kong
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Kumar H, Dugyala VR, Basavaraj MG. Phase Inversion of Ellipsoid-Stabilized Emulsions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:7295-7304. [PMID: 34100620 DOI: 10.1021/acs.langmuir.1c00456] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The efficacy of anisotropic particles in Pickering emulsion stabilization, attributed to shape-induced capillary interactions, is well-documented in the literature. In this contribution, we show that the surface of hematite ellipsoids can be modified in situ by the addition of oleic acid to effect transitional phase inversion of Pickering emulsions. Interestingly, incorporation of oleic acid results in the formation of nonspherical emulsion drops. The phase inversion of oil-in-water to water-in-oil and the transition in shape of emulsion drops from spherical to nonspherical is observed in two different particle systems, namely, nanoellipsoids and microellipsoids. The surface of spherical emulsion drops stabilized by particles or particles along with high concentration of oleic acid is found to consist of ellipsoids arranged in a close-packed configuration with their major axis parallel to the interface. In contrast, at intermediate oleic acid concentration, the surface of nonspherical emulsion drops is observed to be covered with loosely packed particle monolayer, with the ellipsoids at the oil/water interface taking up many different orientations. Using contact angle goniometry, the change in the wettability of hematite particles due to adsorption of oleic acid is established to be the mechanism responsible for the phase inversion of Pickering emulsions.
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Affiliation(s)
- Hemant Kumar
- Polymer Engineering and Colloid Science(PECS) Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai - 600036, Tamil Nadu, India
| | - Venkateshwar Rao Dugyala
- Department of Chemical Engineering, Indian Institute of Science Education and Research Bhopal, Bhopal 462 066 Madhya Pradesh, India
| | - Madivala G Basavaraj
- Polymer Engineering and Colloid Science(PECS) Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai - 600036, Tamil Nadu, India
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Whey Protein Isolate Microgel Properties Tuned by Crosslinking with Organic Acids to Achieve Stabilization of Pickering Emulsions. Foods 2021; 10:foods10061296. [PMID: 34199941 PMCID: PMC8226977 DOI: 10.3390/foods10061296] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/30/2021] [Accepted: 06/01/2021] [Indexed: 11/16/2022] Open
Abstract
Whey protein isolate (WPI) can be used effectively to produce food-grade particles for stabilizing Pickering emulsions. In the present study, crosslinking of WPI microgels using organic acids (tannic and citric acids) is proposed to improve their functionality in emulsions containing roasted coffee oil. It was demonstrated that crosslinking of WPI by organic acids reduces the microgels’ size from ≈1850 nm to 185 nm and increases their contact angle compared to conventional WPI microgels, achieving values as high as 60°. This led to the higher physical stability of Pickering emulsions: the higher contact angle and smaller particle size of acid-crosslinked microgels contribute to the formation of a thinner layer of particles on the oil/water (O/W) interface that is located mostly in the water phase, thus forming an effective barrier against droplet coalescence. Particularly, emulsions stabilized by tannic acid-crosslinked WPI microgels presented neither creaming nor sedimentation up to 7 days of storage. The present work demonstrates that the functionality of these crosslinked WPI microgels can be tweaked considerably, which is an asset compared to other food-grade particles that mostly need to be used as such to comply with the clean-label policy. In addition, the applications of these particles for an emulsion are much more diverse as of the starting material.
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Shahid S, Basavaraj MG. Controlling the microstructure of emulsions by exploiting particle-polyelectrolyte association. J Colloid Interface Sci 2021; 597:409-421. [PMID: 33895698 DOI: 10.1016/j.jcis.2021.03.148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/05/2021] [Accepted: 03/25/2021] [Indexed: 11/20/2022]
Abstract
HYPOTHESIS Albeit solid stabilized emulsions are studied for several decades, the surface of the emulsion drops most often are coated with densely packed and jammed monolayer of particles. However, a control over the area that the particles occupy on the drop surface is necessary, especially in applications involving controlled release of active compounds from emulsions. We hypothesize that it is possible to achieve precise control over the concentration of particles on the surface of emulsions by tailoring the adsorption of different species in a multi-component dispersion used for emulsification. EXPERIMENTS To this end, we carry out emulsification of oil and aqueous dispersions consisting of a combination of oppositely charged colloidal particles and polyelectrolyte. The droplet size distribution and storage stability of the oil-in-water emulsions, the microstructure, the percentage area of the drop surface occupied by the particles and the adsorption behavior of particle-polyelectrolyte binary dispersions are investigated. FINDINGS Our results demonstrate that the association between oppositely charged colloidal particles and polyelectrolyte can be exploited to obtain surface active species that aid in the formation of emulsions. Moreover, we found that the concentration of particle-polyelectrolyte complexes and polyelectrolyte in the dispersions used in emulsification greatly influence the mean diameter of the emulsions and their microstructure. Our findings provide a strategy to achieve control over surface coverage of particles on the emulsion droplets across a wide range - from a theoretically possible maximum, ≈90%, to as low as ≈5%. Interestingly, the emulsions formulated are found to possess excellent storage stability irrespective of the particle coverage on the drop surface.
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Affiliation(s)
- Shumaila Shahid
- Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai - 600036, Tamil Nadu, India
| | - Madivala G Basavaraj
- Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai - 600036, Tamil Nadu, India.
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Bazazi P, Hejazi SH. Cellulose Nanocrystal Laden Oil–Water Interfaces: Interfacial Viscoelasticity, Emulsion Stability, and the Dynamics of Three-Phase Contact-Lines. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c00413] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Parisa Bazazi
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - S. Hossein Hejazi
- Department of Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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19
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Jia K, Guo Y, Yu Y, Zhang J, Yu L, Wen W, Mai Y. pH-Responsive Pickering emulsions stabilized solely by surface-inactive nanoparticles via an unconventional stabilization mechanism. SOFT MATTER 2021; 17:3346-3357. [PMID: 33630989 DOI: 10.1039/d1sm00081k] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Using solely highly hydrophilic particles to stabilize emulsions, especially high internal phase emulsions, has always been an important challenge. Here pH-responsive Pickering emulsions stabilized by a low concentration of bare highly hydrophilic Ludox CL nanoparticles without surface modification or addition of surfactants are developed at neutral pH. The dispersed nanoparticles can be transformed into an aggregate state with a network-like structure near the isoelectric point, which contributes to the stabilization of the emulsions. Moreover, the vdW attraction between particles and droplets also plays a key role in the formation of emulsions, which can make the aggregated nanoparticles adsorb tightly around the droplets rather than penetrate the oil-water interface. The formed protective armor and network-like aggregates separate droplets from each other to prevent coalescence. At a low nanoparticle concentration (0.5 wt%), a high internal phase emulsion can be formed and can last up to half a year. This system can emulsify not only the hydrocarbon oil but also the fluoroalkane oil phase. Finally, organic-inorganic composite particles are fabricated using the template action of the Pickering emulsions. The method of preparing composite particles is more convenient than the traditional Pickering emulsion polymerization which often requires the modification of the surface of the hydrophilic particles or the addition of auxiliary monomers. This study provides a simple green strategy for the preparation of a more stable Pickering emulsion stabilized by surface-inactive nanoparticles and will broaden the scope of applications.
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Affiliation(s)
- Kangle Jia
- Guangdong Provincial Key Laboratory of Industrial Surfactant, Institute of Chemical Engineering, Guangdong Academy of Sciences, Guangzhou 510000, Guangdong, P. R. China.
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20
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Biomolecule-based pickering food emulsions: Intrinsic components of food matrix, recent trends and prospects. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2020.106303] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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21
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Pickering emulsions stabilized by surfactant particles with smart responses to pH and metal-ligands. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.114730] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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22
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Jia H, Wu H, Wei X, Han Y, Wang Q, Song J, Dai J, Yan H, Liu D. Investigation on the effects of AlOOH nanoparticles on sodium dodecylbenzenesulfonate stabilized o/w emulsion stability for EOR. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.125278] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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23
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Chen L, Ao F, Ge X, Shen W. Food-Grade Pickering Emulsions: Preparation, Stabilization and Applications. Molecules 2020; 25:E3202. [PMID: 32674301 PMCID: PMC7397194 DOI: 10.3390/molecules25143202] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/10/2020] [Accepted: 07/11/2020] [Indexed: 01/14/2023] Open
Abstract
In recent years, Pickering emulsions have emerged as a new method and have attracted much attention in the fields of food sciences. Unlike conventional emulsions, Pickering emulsions are stabilized by solid particles, which can irreversibly adsorb on the oil-water interface to form a dense film to prevent the aggregation of droplets. The research and development of food-grade solid particles are increasingly favored by scientific researchers. Compared with conventional emulsions, Pickering emulsions have many advantages, such as fewer using amounts of emulsifiers, biocompatibility and higher safety, which may offer feasibility to have broad application prospects in a wide range of fields. In this article, we review the preparation methods, stabilization mechanism, degradation of Pickering emulsions. We also summarize its applications in food sciences in recent years and discuss its future prospects and challenges in this work.
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Affiliation(s)
- Lijuan Chen
- Department of Food Science and Technology, College of Light Industry Science and Engineering, Nanjing Forestry University, Nanjing 210037, China;
| | - Fen Ao
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi’an 710000, China;
| | - Xuemei Ge
- Department of Food Science and Technology, College of Light Industry Science and Engineering, Nanjing Forestry University, Nanjing 210037, China;
| | - Wen Shen
- School of Food and Biological Engineering, Shaanxi University of Science & Technology, Xi’an 710000, China;
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24
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Gruber I, Nuhnen A, Lerch A, Nießing S, Klopotowski M, Herbst A, Karg M, Janiak C. Synthesis of Nano/Microsized MIL-101Cr Through Combination of Microwave Heating and Emulsion Technology for Mixed-Matrix Membranes. Front Chem 2019; 7:777. [PMID: 31803718 PMCID: PMC6877507 DOI: 10.3389/fchem.2019.00777] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 10/28/2019] [Indexed: 01/30/2023] Open
Abstract
Nano/microsized MIL-101Cr was synthesized by microwave heating of emulsions for the use as a composite with Matrimid mixed-matrix membranes (MMM) to enhance the performance of a mixed-gas-separation. As an example, we chose CO2/CH4 separation. Although the incorporation of MIL-101Cr in MMMs is well-known, the impact of nanosized MIL-101Cr in MMMs is new and shows an improvement compared to microsized MIL-101Cr under the same conditions and mixed-gas permeation. In order to reproducibly obtain nanoMIL-101Cr microwave heating was supplemented by carrying out the reaction of chromium nitrate and 1,4-benzenedicarboxylic acid in heptane-in-water emulsions with the anionic surfactant sodium oleate as emulsifier. The use of this emulsion with the phase inversion temperature (PIT) method offered controlled nucleation and growth of nanoMIL-101 particles to an average size of <100 nm within 70 min offering high apparent BET surface areas (2,900 m2 g-1) and yields of 45%. Concerning the CO2/CH4 separation, the best result was obtained with 24 wt.% of nanoMIL-101Cr@Matrimid, leading to 32 Barrer in CO2 permeability compared to six Barrer for the neat Matrimid polymer membrane and 21 Barrer for the maximum possible 20 wt.% of microMIL-101Cr@Matrimid. The nanosized filler allowed reaching a higher loading where the permeability significantly increased above the predictions from Maxwell and free-fractional-volume modeling. These improvements for MMMs based on nanosized MIL-101Cr are promising for other gas separations.
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Affiliation(s)
- Irina Gruber
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Alexander Nuhnen
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Arne Lerch
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Sandra Nießing
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Maximilian Klopotowski
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Annika Herbst
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Matthias Karg
- Institut für Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Christoph Janiak
- Institut für Anorganische Chemie und Strukturchemie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
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25
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Huang F, Liang Y, He Y. On the Pickering emulsions stabilized by calcium carbonate particles with various morphologies. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.123722] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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26
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Zou J, Liu Y, Wang Q, Liu H, Jia H, Lian P. The Effects of Dynamic Noncovalent Interaction between Surfactants and Additional Salt on the pH‐Switchable Interfacial Tension Variations. J SURFACTANTS DETERG 2019. [DOI: 10.1002/jsde.12342] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jian Zou
- Bohai Oilfield Research Institute, Tianjin BranchCNOOC China Limited Tianjin 300459 China
| | - Yigang Liu
- Bohai Oilfield Research Institute, Tianjin BranchCNOOC China Limited Tianjin 300459 China
| | - Qiuxia Wang
- Bohai Oilfield Research Institute, Tianjin BranchCNOOC China Limited Tianjin 300459 China
| | - Hao Liu
- Bohai Oilfield Research Institute, Tianjin BranchCNOOC China Limited Tianjin 300459 China
| | - Han Jia
- Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China))Ministry of Education Qingdao 266580 China
- Shandong Key Laboratory of Oilfield Chemistry, School of Petroleum EngineeringChina University of Petroleum (East China) Qingdao 266580 China
| | - Peng Lian
- Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China))Ministry of Education Qingdao 266580 China
- Shandong Key Laboratory of Oilfield Chemistry, School of Petroleum EngineeringChina University of Petroleum (East China) Qingdao 266580 China
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27
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Zhang Y, Chen K, Cao L, Li K, Wang Q, Fu E, Guo X. Stabilization of Pickering Emulsions by Hairy Nanoparticles Bearing Polyanions. Polymers (Basel) 2019; 11:E816. [PMID: 31067697 PMCID: PMC6571738 DOI: 10.3390/polym11050816] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/13/2019] [Accepted: 04/28/2019] [Indexed: 11/23/2022] Open
Abstract
Pickering emulsions are increasingly applied in drug delivery, oil-water separation, composite materials preparation, and other fields. However, systematic studies on the stabilization of Pickering emulsions to satisfy the growing application demands in multiple fields with long-term conservation are rare. Compared to conventional solid nanoparticles, polyanion-modified hairy nanoparticles are more stable in practical environments and are investigated in this study. Poly (sodium p-styrenesulfonate) was grafted to a polystyrene (PS) core via a photoemulsion polymerization. A hairy nanoparticle bearing polyanions called poly (sodium p-styrenesulfonate) brush (PS@PSS) was synthesized. The size and uniformity of the Pickering emulsions stabilized by PS@PSS were investigated via a polarizing microscope. The stability of Pickering emulsions were optimized by adjusting critical factors like ultrasonic power and time, standing time, oil phases, salt concentration, and water:oil ratio. Results indicated that the Pickering emulsions could be stabilized by PS@PSS nanoparticles, which showed remarkable and adjustable partial wetting properties. It was found that the optimized conditions were ultrasonic power of 150 W, ultrasonic time of 3 min, salt concentration of 0.1 mM, oil phase of hexadecane, and water:oil ratio of 1:1. The formation and stability of Pickering emulsion are closely related to the hairy poly (sodium p-styrenesulfonate) brush layer on the nanoparticle surface.
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Affiliation(s)
- Ying Zhang
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.
| | - Kaimin Chen
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
| | - Lan Cao
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.
| | - Kai Li
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
| | - Qiaoling Wang
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
| | - Enyu Fu
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
| | - Xuhong Guo
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China.
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28
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Jiang Q, Sun N, Li Q, Si W, Li J, Li A, Gao Z, Wang W, Wang J. Redox-Responsive Pickering Emulsions Based on Silica Nanoparticles and Electrochemical Active Fluorescent Molecules. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:5848-5854. [PMID: 30964688 DOI: 10.1021/acs.langmuir.9b00250] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In this paper, we report a novel redox-responsive water-in-oil Pickering emulsion stabilized by negatively charged silica nanoparticles in combination with a trace amount of redox switchable fluorescent molecule ferrocene azine (FcA), in which ferrocene serves as a redox-sensitive group and anthryl unit serves as a fluorescence emission center. By alternately adding oxidants and reducing agents at a moderate condition, the amphiphilicity of silica nanoparticles changes because of the adsorption of Fc+A and the desorption of FcA on the silica surface. On the one hand, the stability of emulsions can be transformed between stable and unstable at ambient temperature via redox trigger and the regulation process can be cycled at least three times. On the other hand, the fluorescent intensity of the FcA molecule can be regulated by redox stimuli; thus, the change in fluorescent behavior of the emulsion droplets is observed upon redox cycles, which makes it useful in the fluorescent label of stimuli-responsive Pickering emulsions. This work provides a deep understanding of the regulation mechanism of Pickering emulsions upon redox stimuli and opens the new way for in situ fluorescent label of stimulus-responsive Pickering emulsions without introducing additional fluorescent molecules.
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Affiliation(s)
- Qiuyan Jiang
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Ning Sun
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Qiuhong Li
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Weimeng Si
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Jiao Li
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Aixiang Li
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Zengli Gao
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Weiwei Wang
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
| | - Jiarui Wang
- School of Materials Science and Engineering , Shandong University of Technology , Zibo , Shandong 255049 , P. R. China
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