Phase behaviour and droplet size of oil-in-water Pickering emulsions stabilised with plant-derived nanocellulosic materials

AbstractPickering emulsions (emulsions stabilized by solid-state additives) are attractive as they have strong similarities with traditional surfactant-based emulsions. In this study, an oil-in-water (O/W) paraffin Pickering emulsion system with satisfying stability and small droplet size distribution was developed by hydrophilic silica particles and traditional surfactants as mixed emulsifiers. The droplet morphology and size distribution were observed by optical microscopy and a laser particle analyzer. The emulsion stability was improved and the droplet size was reduced after addition of a suitable amount of silica particles. The silica concentration of 1% showed the optimal effect among all the levels observed (0.1, 0.5, 1 and 2%). Wood was impregnated with the prepared emulsion, and the chemical and morphological properties of the product were investigated by Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) combined with energy-dispersed X-ray analysis (SEM-EDXA). Moreover, the hydrophobicity, thermal properties, surface hardness, axial compression strength (CS) and dynamic mechanical properties were tested. The silica was evenly distributed in the wood cell wall and thus there was a synergistic positive effect from the paraffin and silica in the cell wall leading to better hydrophobicity, improved surface hardness and mechanical properties including the thermal stability.

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Surfactant-Free Cellulose Filaments Stabilized Oil in Water Emulsions

10.21203/rs.3.rs-374430/v1 ◽

2021 ◽

Author(s):

Amir Varamesh ◽

Ragesh Prathapan ◽

Ali Telmadarreie ◽

Jia Li ◽

Keith Gourlay ◽

...

Keyword(s):

Droplet Size ◽

Fluorescent Protein ◽

Fluorescent Microscopy ◽

Cellulose Nanofibrils ◽

Continuous Phase ◽

Carbohydrate Binding ◽

Pickering Emulsions ◽

Cellulosic Material ◽

Oil In Water ◽

Wide Range

Abstract There has been significant interest over recent years in the production and application of sustainable and green materials. Among these, nanocellulose has incurred great interest because of its exceptional properties and wide range of potential applications, including in Pickering emulsions. However, the production cost of these cellulosic materials has limited their application. In this study, the capability of a new type of cheaper cellulosic material, cellulose filaments (CFs), in formulating stable oil in water Pickering emulsions was investigated and compared with three conventional nanocelluloses, namely cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs (TEMPO-CNFs). Results showed that CFs can provide stable surfactant-free emulsions over wide ranges of salt concentration (0 – 500 mM) and pH (2 – 10), as indicated by the near constant oil droplet size and dewatering index of the emulsions. This is due to the ability of CFs to strongly adsorb to the oil and water interface, as evidenced by visualizing labeled CFs with engineered carbohydrate-binding module (CBM2a) conjugated with green fluorescent protein (CBM2a-eGFP) under fluorescent microscopy. Compared to the emulsions stabilized by other types of nanocelluloses, the CFs-stabilized emulsion demonstrated a larger average droplet size and comparable (with CNFs) or better (than CNCs and TEMPO-CNFs) stability, which is partially attributed to the higher viscosity of continuous phase in the presence of CFs. The results of this study demonstrate the use of CFs as a novel and cheaper cellulosic material for stabilizing emulsions, which opens the door to a range of markets from the food industry to engineering applications.

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Single-Conidium Encapsulation in Oil-in-Water Pickering Emulsions at High Encapsulation Yield

Frontiers in Chemistry ◽

10.3389/fchem.2021.726874 ◽

2021 ◽

Vol 9 ◽

Author(s):

Liliya Kotliarevski ◽

Karthik Ananth Mani ◽

Reut Amar Feldbaum ◽

Noga Yaakov ◽

Eduard Belausov ◽

...

Keyword(s):

Confocal Microscopy ◽

Droplet Size ◽

Pickering Emulsion ◽

Mineral Oil ◽

High Yield ◽

Pickering Emulsions ◽

Amine Functionalized ◽

Oil In Water ◽

The Stability

This study presents an individual encapsulation of fungal conidia in an oil-in-water Pickering emulsion at a single-conidium encapsulation yield of 44%. The single-conidium encapsulation yield was characterized by analysis of confocal microscopy micrographs. Mineral oil-in-water emulsions stabilized by amine-functionalized titania dioxide (TiO2-NH2 or titania-NH2) particles were prepared. The structure and the stability of the emulsions were investigated at different compositions by confocal microscopy and a LUMiSizer® respectively. The most stable emulsions with a droplet size suitable for single-conidium encapsulation were further studied for their individual encapsulation capabilities. The yields of individual encapsulation in the emulsions; i.e., the number of conidia that were individually encapsulated out of the total number of conidia, were characterized by confocal microscopy assay. This rapid, easy to use approach to single-conidium encapsulation, which generates a significantly high yield with eco-friendly titania-based emulsions, only requires commonly used emulsification and agitation methods.

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Stabilization and Release of Palm Tocotrienol Emulsion Fabricated Using pH-Sensitive Calcium Carbonate

Foods ◽

10.3390/foods10020358 ◽

2021 ◽

Vol 10 (2) ◽

pp. 358

Author(s):

Phui Yee Tan ◽

Beng Ti Tey ◽

Eng Seng Chan ◽

Oi Ming Lai ◽

Hon Weng Chang ◽

...

Keyword(s):

Calcium Carbonate ◽

Droplet Size ◽

Entrapment Efficiency ◽

Ph Sensitive ◽

Emulsion System ◽

Ph Responsive ◽

Small Droplet ◽

Homogenization Time ◽

Oil In Water ◽

Ph Range

Calcium carbonate (CaCO3) has been utilized as a pH-responsive component in various products. In this present work, palm tocotrienols-rich fraction (TRF) was successfully entrapped in a self-assembled oil-in-water (O/W) emulsion system by using CaCO3 as the stabilizer. The emulsion droplet size, viscosity and tocotrienols entrapment efficiency (EE) were strongly affected by varying the processing (homogenization speed and time) and formulation (CaCO3 and TRF concentrations) parameters. Our findings indicated that the combination of 5000 rpm homogenization speed, 15 min homogenization time, 0.75% CaCO3 concentration and 2% TRF concentration resulted in a high EE of tocotrienols (92.59–99.16%) and small droplet size (18.83 ± 1.36 µm). The resulting emulsion system readily released the entrapped tocotrienols across the pH range tested (pH 1–9); with relatively the highest release observed at pH 3. The current study presents a potential pH-sensitive emulsion system for the entrapment and delivery of palm tocotrienols.

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Characteristics and application of fish oil-in-water pickering emulsions structured with tea water-insoluble proteins/κ-carrageenan complexes

Food Hydrocolloids ◽

10.1016/j.foodhyd.2020.106562 ◽

2021 ◽

Vol 114 ◽

pp. 106562

Author(s):

Zhongyang Ren ◽

Zhanming Li ◽

Zhongzheng Chen ◽

Yuanyuan Zhang ◽

Xiaorong Lin ◽

...

Keyword(s):

Fish Oil ◽

Pickering Emulsions ◽

Oil In Water

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Fluorescent liquid pyrene derivative-in-water microemulsions

Chemical Communications ◽

10.1039/c6cc01517d ◽

2016 ◽

Vol 52 (46) ◽

pp. 7344-7347 ◽

Cited By ~ 24

Author(s):

M. J. Hollamby ◽

A. E. Danks ◽

Z. Schnepp ◽

S. E. Rogers ◽

S. R. Hart ◽

...

Keyword(s):

Droplet Size ◽

Fluorescence Emission ◽

Oil In Water

Using a liquid pyrene derivative as the oil, stable oil-in-water microemuslions are prepared, with tunable fluorescence emission via droplet size.

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An Oligoimide Particle as a Pickering Emulsion Stabilizer

Polymers ◽

10.3390/polym10101071 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1071 ◽

Cited By ~ 3

Author(s):

Yu-Jin Cho ◽

Dong-Min Kim ◽

In-Ho Song ◽

Ju-Young Choi ◽

Seung-Won Jin ◽

...

Keyword(s):

Particle Concentration ◽

Pickering Emulsion ◽

Pickering Emulsions ◽

Step Method ◽

Wetting Properties ◽

Emulsion Droplets ◽

Step Procedure ◽

Oil In Water ◽

One Step ◽

Oil Emulsions

A pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA)-based oligoimide (PMDA-ODA) was synthesized by a one-step procedure using water as a solvent. The PMDA-ODA particles showed excellent partial wetting properties and were stably dispersed in both water and oil phases. A stable dispersion was not obtained with comparison PMDA-ODA particles that were synthesized by a conventional two-step method using an organic solvent. Both oil-in-water and water-in-oil Pickering emulsions were prepared using the oligoimide particles synthesized in water, and the size of the emulsion droplet was controlled based on the oligoimide particle concentration. The oligoimide particles were tested to prepare Pickering emulsions using various kinds of oils. The oil-in-water Pickering emulsions were successfully applied to prepare microcapsules of the emulsion droplets. Our new Pickering emulsion stabilizer has the advantages of easy synthesis, no need for surface modification, and the capability of stabilizing both oil-in-water and water-in-oil emulsions.

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In situ Fabrication of Multi-Walled Carbon Nanotubes/Silica Hybrid Colloidosomes by Pickering Emulsion Templating Using Trialkoxysilanes of Opposite Polarity

Polymers ◽

10.3390/polym11091480 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1480 ◽

Cited By ~ 1

Author(s):

Grzegorzewski ◽

Benhaim ◽

Alkotzer ◽

Zelinger ◽

Yaakov ◽

...

Keyword(s):

Carbon Nanotubes ◽

Silica Nanoparticles ◽

Droplet Size ◽

Opposite Polarity ◽

Pickering Emulsions ◽

Volume Percentage ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Emulsion Templating ◽

Silica Hybrid

A simple and effective way to prepare multi-walled carbon nanotubes (MWNT)//silica hybrid microcapsules (colloidosomes) is presented. These microcapsules have been generated by emulsion templating in a biphasic oil-in-water (o/w) system. Two trialkoxysilanes of complementary polarity, (3-aminopropyl)triethoxysilane (APTES) and dodecyltriethoxysilane (DTES), were used to chemically immobilize the silica nanoparticles at the o/w interface and stabilize the as-generated Pickering emulsions. The effects of varying the o/w ratio and the concentration of the added solids on the type of emulsion formed, the oil droplet size, as well as the emulsion stability have been investigated. The emulsion phase fraction was dependent on the silica content while the droplet size increased with increasing oil volume percentage. A solid shell emerged around the oil droplets from copolymerization between silane monomers. The thickness of the resulting shells was several hundreds of nm. Although MWNTs and silica nanoparticles both were co-assembled at the o/w interface, silica has shown to be the sole stabilizer, with APTES being crucial for the formation of the shell structure. Drop-casting of the emulsion and air-drying led to hierarchical open porous MWNT-silica nanocomposites. These new structures are promising as electrically conductive thin films for variety of applications, such as electro-optics, encapsulation, or chemical sensing.

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New Trends in Natural Emulsifiers and Emulsion Technology for the Food Industry

10.5772/intechopen.99892 ◽

2021 ◽

Author(s):

Arantzazu Santamaria-Echart ◽

Isabel P. Fernandes ◽

Samara C. Silva ◽

Stephany C. Rezende ◽

Giovana Colucci ◽

...

Keyword(s):

Circular Economy ◽

Food Industry ◽

Solid Particles ◽

Microbial Fermentation ◽

Bibliometric Data ◽

Pickering Emulsions ◽

Double Emulsions ◽

Oil In Water ◽

Food Applications ◽

New Generation

The food industry depends on using different additives, which increases the search for effective natural or natural-derived solutions, to the detriment of the synthetic counterparts, a priority in a biobased and circular economy scenario. In this context, different natural emulsifiers are being studied to create a new generation of emulsion-based products. Among them, phospholipids, saponins, proteins, polysaccharides, biosurfactants (e.g., compounds derived from microbial fermentation), and organic-based solid particles (Pickering stabilizers) are being used or start to gather interest from the food industry. This chapter includes the basic theoretical fundamentals of emulsions technology, stabilization mechanisms, and stability. The preparation of oil-in-water (O/W) and water-in-oil (W/O) emulsions, the potential of double emulsions, and the re-emerging Pickering emulsions are discussed. Moreover, the most relevant natural-derived emulsifier families (e.g., origin, stabilization mechanism, and applications) focusing food applications are presented. The document is grounded in a bibliographic review mainly centered on the last 10-years, and bibliometric data was rationalized and used to better establish the hot topics in the proposed thematic.

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