Enhancing reaction rate in a Pickering emulsion system with natural magnetotactic bacteria as nanoscale magnetic stirring bars

Pickering emulsion systems have created new opportunities for two-phase biocatalysis, however their catalytic performance is often hindered by biphasic mass transfer process relying on the interfacial area. In this study, lipase-immobilized mesoporous silica particles (LMSPs) are employed as both Pickering stabilizers and biocatalysts. A series of alkyl silanes with the different carbon length are used to modify LMSPs to obtain suitable wettability and enlarge the interfacial area of Pickering emulsion. The results show the water/paraffin oil Pickering emulsions stabilized by 8 carbon atoms silane grafted LMSPs (LMSPs_C8) with a three-phase contact angles of 95° get the relatively large interfacial area. Moreover, the conversion of enzymatic reaction catalyzed by LMSPs_C8 Pickering emulsion system is 3.4 times higher than that unmodified LMSPs with the reaction time of 10 min. Additionally, the effective recycling of LMSPs is achieved by simple low-speed centrifugation. As evidenced by a 6-cycles reaction of remaining 75% of relative enzymatic activity, the protection of 350–450 nm mesoporous silica particles can alleviate the inactivation of enzyme from the shear stress and make a benefit to form stabile Pickering emulsion. Therefore, the biphasic reactions in the Pickering emulsion system can be effectively enhanced through changing interfacial area only by the means of adjusting the wettability of biocatalysts.

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Interfacial biocatalysis in bacteria-stabilized Pickering emulsions for microbial transformation of hydrophobic chemicals

Catalysis Science & Technology ◽

10.1039/d0cy02243h ◽

2021 ◽

Author(s):

Haisheng Xie ◽

Wenyu Zhao ◽

Daniel Chikere Ali ◽

Xuehong Zhang ◽

Zhilong Wang

Keyword(s):

Microbial Transformation ◽

Pickering Emulsion ◽

Pickering Emulsions

The Pickering emulsion interface is an exceptional habitat for bacteria to grow by simultaneously utilizing hydrophobic and hydrophilic chemicals.

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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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Stimuli-responsive Pickering emulsions: recent advances and potential applications

Soft Matter ◽

10.1039/c5sm00247h ◽

2015 ◽

Vol 11 (18) ◽

pp. 3512-3529 ◽

Cited By ~ 282

Author(s):

Juntao Tang ◽

Patrick James Quinlan ◽

Kam Chiu Tam

Keyword(s):

Magnetic Field ◽

Ionic Strength ◽

Light Intensity ◽

Magnetic Field Intensity ◽

Pickering Emulsion ◽

Pickering Emulsions ◽

Stimuli Responsive ◽

Comprehensive Review ◽

Potential Applications ◽

Emulsion Systems

Pickering emulsions with stimuli-responsive properties have, in recent years, received a considerable amount of attention. This paper provides a concise and comprehensive review of Pickering emulsion systems that possess the ability to respond to an array of external triggers, including pH, temperature, CO2concentration, light intensity, ionic strength, and magnetic field intensity.

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Optimization of Fluconazole Pickering Emulsion Using Taguchi Orthogonal Array Design

Dhaka University Journal of Pharmaceutical Sciences ◽

10.3329/dujps.v19i2.50633 ◽

2020 ◽

Vol 19 (2) ◽

pp. 169-178

Author(s):

D Prasanthi ◽

N Varsha Priya ◽

Amoolya Chennuri ◽

PK Lakshmi

Keyword(s):

Orthogonal Array ◽

Free Particle ◽

Coconut Oil ◽

Topical Delivery ◽

Pickering Emulsion ◽

Homogenization Method ◽

Sesame Oil ◽

Pickering Emulsions ◽

Independent Variables ◽

Dependent Variables

Emulsifier-free, particle-stabilised emulsions called Pickering emulsions of fluconazole for topical delivery, were studied using Taguchi L9 orthogonal array (OA) design. Formulations were prepared by homogenization method, using bentonite in the concentration range of 2-4% w/v, oil phase (coconut oil, oleic acid, sesame oil). In Taguchi L9 OA experimental design, independent variables (oil phase & concentration of bentonite) effect on dependent variables (drug content & release rate) was studied. All the formulations have shown good physicochemical properties. The PS3 formulation containing sesame oil and 4% bentonite was optimized as particle size was found to be 758.0 nm, zeta potential -48 mv, with Q8 of 166.70±0.15μg/cm2, flux of 17.33±0.02 μg/cm2/hr, permeability coefficient of 3.46±0.015 cm/hr×10-3 and skin content of 4.01±0.24 mg/g. The formulations were stable and non-irritant. Hence pickering emulsion of fluconazole using sesame oil can be used for topical delivery as the drug release was maintained at the localised site. Dhaka Univ. J. Pharm. Sci. 19(2): 169-178, 2020 (December)

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Effect of NaCl concentration on stability of a polymer–Ag nanocomposite based Pickering emulsion: validation via rheological analysis with varying temperature

RSC Advances ◽

10.1039/d0ra03199b ◽

2020 ◽

Vol 10 (36) ◽

pp. 21545-21560

Author(s):

Ramesh Narukulla ◽

Umaprasana Ojha ◽

Tushar Sharma

Keyword(s):

Pickering Emulsion ◽

Pickering Emulsions ◽

Rheological Analysis ◽

Nacl Concentration ◽

The Impact

Schematic for the impact of NaCl on droplet stabilization in Pickering emulsions.

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A novel Pickering emulsion system as the carrier of tocopheryl acetate for its application in cosmetics

Materials Science and Engineering C ◽

10.1016/j.msec.2019.110503 ◽

2020 ◽

Vol 109 ◽

pp. 110503 ◽

Cited By ~ 1

Author(s):

Yun-shan Wei ◽

Zhi-cheng Niu ◽

Feng-qi Wang ◽

Kun Feng ◽

Min-hua Zong ◽

...

Keyword(s):

Pickering Emulsion ◽

Tocopheryl Acetate ◽

Emulsion System

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Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.11.257 ◽

2015 ◽

Vol 11 ◽

pp. 2355-2364 ◽

Cited By ~ 10

Author(s):

Shintaro Kawano ◽

Toshiyuki Kida ◽

Mitsuru Akashi ◽

Hirofumi Sato ◽

Motohiro Shizuma ◽

...

Keyword(s):

Colloidal Particles ◽

Adsorption Property ◽

Building Blocks ◽

Pickering Emulsion ◽

Surface Active Property ◽

Water Interface ◽

Pickering Emulsions ◽

Surface Active ◽

Oil Water ◽

Interfacial Adsorption

Background: Emulsions stabilized by colloidal particles are known as Pickering emulsions. To date, soft microgel particles as well as inorganic and organic particles have been utilized as Pickering emulsifiers. Although cyclodextrin (CD) works as an attractive emulsion stabilizer through the formation of a CD–oil complex at the oil–water interface, a high concentration of CD is normally required. Our research focuses on an effective Pickering emulsifier based on a soft colloidal CD polymer (CD nanogel) with a unique surface-active property. Results: CD nanogels were prepared by crosslinking heptakis(2,6-di-O-methyl)-β-cyclodextrin with phenyl diisocyanate and subsequent immersion of the resulting polymer in water. A dynamic light scattering study shows that primary CD nanogels with 30–50 nm diameter assemble into larger CD nanogels with 120 nm diameter by an increase in the concentration of CD nanogel from 0.01 to 0.1 wt %. The CD nanogel has a surface-active property at the air–water interface, which reduces the surface tension of water. The CD nanogel works as an effective Pickering emulsion stabilizer even at a low concentration (0.1 wt %), forming stable oil-in-water emulsions through interfacial adsorption by the CD nanogels. Conclusion: Soft CD nanogel particles adsorb at the oil–water interface with an effective coverage by forming a strong interconnected network and form a stable Pickering emulsion. The adsorption property of CD nanogels on the droplet surface has great potential to become new microcapsule building blocks with porous surfaces. These microcapsules may act as stimuli-responsive nanocarriers and nanocontainers.

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Preparation of a synergistically stabilized oil-in-water paraffin Pickering emulsion for potential application in wood treatment

Holzforschung ◽

10.1515/hf-2017-0154 ◽

2018 ◽

Vol 72 (6) ◽

pp. 489-497 ◽

Cited By ~ 5

Author(s):

Jun Jiang ◽

Jinzhen Cao ◽

Wang Wang ◽

Haiying Shen

Keyword(s):

Mechanical Properties ◽

Cell Wall ◽

Size Distribution ◽

Droplet Size ◽

Surface Hardness ◽

Pickering Emulsion ◽

Silica Particles ◽

Morphological Properties ◽

Pickering Emulsions ◽

Oil In Water

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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pH-Responsive Pickering emulsion stabilized by polymer-coated silica nanoaggregates and applied to recyclable interfacial catalysis

RSC Advances ◽

10.1039/d0ra07957j ◽

2020 ◽

Vol 10 (69) ◽

pp. 42423-42431

Author(s):

Ruidong Luo ◽

Jinfeng Dong ◽

Yunbai Luo

Keyword(s):

Diblock Copolymer ◽

Trifluoroacetic Acid ◽

Fumed Silica ◽

Pickering Emulsion ◽

Emulsion System ◽

Ph Responsive ◽

Interfacial Catalysis

We synthesized a diblock copolymer and grafted it onto fumed silica in the presence of trifluoroacetic acid to obtain a pH-responsive Pickering emulsion system stabilized by polymer-coated nanoaggregates, P-Si.

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