Special Issue "Membrane Emulsification"

A special issue of Membranes (ISSN 2077-0375). This special issue belongs to the section "Membrane Applications in Industry and Chemical Analysis".

Deadline for manuscript submissions: closed (31 March 2017)

Special Issue Editors

Guest Editor
Dr. Lidietta Giorno

Institute on Membrane Technology, National Research Council, ITM-CNR Via P. Bucci 17/C, 87036 Rende (CS), Italy
Website | E-Mail
Phone: +39 0984 49 2050/2051/2007
Fax: +39 0984 402103
Interests: membrane emulsifier; membrane bioengineering; biocatalytic membrane reactors; integrated membrane systems for bioseparations and bioconversions; integrated membrane operations for water treatment
Guest Editor
Dr. Emma Piacentini

Institute on Membrane Technology, National Research Council, ITM-CNR Via P. Bucci 17/C, 87036 Rende (CS), Italy
Website | E-Mail
Phone: +39 0984 49 2051
Fax: +39 0984 402103
Interests: membrane emulsification; encapsulation; drug delivery; biocatalytic membrane reactors; membrane bioengineering

Special Issue Information

Dear Colleagues,

New production concepts and unit operations are required to promote a sustainable development of a next generation of industrial products and processes based on the use of micro- and nano-particulates with a target size, composition, structure and function.

Membrane emulsification (ME) represents a unique technology, able to produce target droplets by dispersing a non-miscible phase into a continuous phase through a porous membrane on the basis of a drop-by-drop mechanism. Particles from nanometer/submicron to a few hundred microns, including emulsions, spheres, and capsules with a controlled size and composition can be obtained. The distinguishing aspect is that the droplet size is controlled by the choice of the microporous membrane and not by droplets breakup generated by high mechanical stress.

The mild shear stress applied at the pore mouth and the precisely controlled particle size and size distribution, places ME among the most suitable methods for formulations of controlled architectures containing labile bioactive macromolecules. Products deriving from ME processes satisfy market needs for new products with improved quality and functions in critical areas of chemical industry, biotechnology, food, pharmaceutical, and biomedicine.

This Special Issue of Membranes welcomes works related to the topic of Membrane Emulsification Technology. Both original contributions and reviews on recent advances in membrane emulsification, including theoretical and experimental insights in membrane operation methods, membrane emulsification devices, membranes used, as well as application in various fields, are greatly welcome.

Dr. Lidietta Giorno
Dr. Emma Piacentini
Guest Editor

Keywords

  • membrane emulsification (ME)
  • direct membrane emulsification
  • pre-mix membrane emulsificatio
  • cross-flow membrane emulsification
  • dynamic ME
  • static ME
  • droplet formation mechanisms in ME
  • amphiphilic membrane surface properties
  • emulsions
  • capsules
  • spheres
  • uniform-sized particles

Published Papers (5 papers)

View options order results:
result details:
Displaying articles 1-5
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Apparent Interfacial Tension Effects in Protein Stabilized Emulsions Prepared with Microstructured Systems
Received: 26 January 2017 / Revised: 17 March 2017 / Accepted: 21 March 2017 / Published: 25 March 2017
PDF Full-text (1365 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Proteins are mostly used to stabilize food emulsions; however, production of protein containing emulsions is notoriously difficult to capture in scaling relations due to the complex behavior of proteins in interfaces, in combination with the dynamic nature of the emulsification process. Here, we [...] Read more.
Proteins are mostly used to stabilize food emulsions; however, production of protein containing emulsions is notoriously difficult to capture in scaling relations due to the complex behavior of proteins in interfaces, in combination with the dynamic nature of the emulsification process. Here, we investigate premix membrane emulsification and use the Ohnesorge number to derive a scaling relation for emulsions prepared with whey protein, bovine serum albumin (BSA), and a standard emulsifier Tween 20, at various concentrations (0.1%, 0.5%, 1.25% and 2%). In the Ohnesorge number, viscous, inertia, and interfacial tension forces are captured, and most of the parameters can be measured with great accuracy, with the exception of the interfacial tension. We used microfluidic Y-junctions to estimate the apparent interfacial tension at throughputs comparable to those in premix emulsification, and found a unifying relation. We next used this relation to plot the Ohnesorge number versus P-ratio defined as the applied pressure over the Laplace pressure of the premix droplet. The measured values all showed a decreasing Ohnesorge number at increasing P-ratio; the differences between regular surfactants and proteins being systematic. The surfactants were more efficient in droplet size reduction, and it is expected that the differences were caused by the complex behavior of proteins in the interface (visco-elastic film formation). The differences between BSA and whey protein were relatively small, and their behavior coincided with that of low Tween concentration (0.1%), which deviated from the behavior at higher concentrations. Full article
(This article belongs to the Special Issue Membrane Emulsification)
Figures

Figure 1

Open AccessArticle Emulsification Characteristics Using a Dynamic Woven Metal Microscreen Membrane
Received: 23 March 2016 / Revised: 30 May 2016 / Accepted: 13 June 2016 / Published: 20 June 2016
Cited by 1 | PDF Full-text (3489 KB) | HTML Full-text | XML Full-text
Abstract
An oscillatory emulsification system for the production of oil in water emulsions using a commercially available low-cost woven metal microscreen (WMMS) is investigated. The system allows for independent control of both the oscillation frequencies and amplitudes such that it provides two degrees of [...] Read more.
An oscillatory emulsification system for the production of oil in water emulsions using a commercially available low-cost woven metal microscreen (WMMS) is investigated. The system allows for independent control of both the oscillation frequencies and amplitudes such that it provides two degrees of freedom for controlling the emulsion properties. The investigations included the production of both surfactant and particle-stabilized emulsions. The average droplet size was found to decrease when both the oscillation frequency and amplitude was increased. For surfactant-stabilized emulsions, using bi-surfactants in both the continuous and dispersed phases resulted in a smaller droplet size due to lower interfacial tension. For particle-stabilized emulsions, both the hydrodynamics of the system and the hydrophobic and hydrophilic nature of the stabilizing particles influenced the interfacial properties at the oil–water interface, which in turn affected the final droplet size and distribution with potential droplet breakage. In absence of the latter, a simple torque balance model can be used to reasonably predict the average emulsion droplet size. Full article
(This article belongs to the Special Issue Membrane Emulsification)
Figures

Figure 1

Open AccessArticle Production of Fluconazole-Loaded Polymeric Micelles Using Membrane and Microfluidic Dispersion Devices
Received: 31 January 2016 / Revised: 15 May 2016 / Accepted: 18 May 2016 / Published: 25 May 2016
Cited by 4 | PDF Full-text (3202 KB) | HTML Full-text | XML Full-text
Abstract
Polymeric micelles with a controlled size in the range between 41 and 80 nm were prepared by injecting the organic phase through a microengineered nickel membrane or a tapered-end glass capillary into an aqueous phase. The organic phase was composed of 1 mg·mL [...] Read more.
Polymeric micelles with a controlled size in the range between 41 and 80 nm were prepared by injecting the organic phase through a microengineered nickel membrane or a tapered-end glass capillary into an aqueous phase. The organic phase was composed of 1 mg·mL−1 of PEG-b-PCL diblock copolymers with variable molecular weights, dissolved in tetrahydrofuran (THF) or acetone. The pore size of the membrane was 20 μm and the aqueous/organic phase volumetric flow rate ratio ranged from 1.5 to 10. Block copolymers were successfully synthesized with Mn ranging from ~9700 to 16,000 g·mol−1 and polymeric micelles were successfully produced from both devices. Micelles produced from the membrane device were smaller than those produced from the microfluidic device, due to the much smaller pore size compared with the orifice size in a co-flow device. The micelles were found to be relatively stable in terms of their size with an initial decrease in size attributed to evaporation of residual solvent rather than their structural disintegration. Fluconazole was loaded into the cores of micelles by injecting the organic phase composed of 0.5–2.5 mg·mL−1 fluconazole and 1.5 mg·mL−1 copolymer. The size of the drug-loaded micelles was found to be significantly larger than the size of empty micelles. Full article
(This article belongs to the Special Issue Membrane Emulsification)
Figures

Figure 1

Open AccessArticle Microencapsulation by Membrane Emulsification of Biophenols Recovered from Olive Mill Wastewaters
Received: 12 April 2016 / Revised: 3 May 2016 / Accepted: 4 May 2016 / Published: 9 May 2016
Cited by 2 | PDF Full-text (2472 KB) | HTML Full-text | XML Full-text
Abstract
Biophenols are highly prized for their free radical scavenging and antioxidant activities. Olive mill wastewaters (OMWWs) are rich in biophenols. For this reason, there is a growing interest in the recovery and valorization of these compounds. Applications for the encapsulation have increased in [...] Read more.
Biophenols are highly prized for their free radical scavenging and antioxidant activities. Olive mill wastewaters (OMWWs) are rich in biophenols. For this reason, there is a growing interest in the recovery and valorization of these compounds. Applications for the encapsulation have increased in the food industry as well as the pharmaceutical and cosmetic fields, among others. Advancements in micro-fabrication methods are needed to design new functional particles with target properties in terms of size, size distribution, and functional activity. This paper describes the use of the membrane emulsification method for the fine-tuning of microparticle production with biofunctional activity. In particular, in this pioneering work, membrane emulsification has been used as an advanced method for biophenols encapsulation. Catechol has been used as a biophenol model, while a biophenols mixture recovered from OMWWs were used as a real matrix. Water-in-oil emulsions with droplet sizes approximately 2.3 times the membrane pore diameter, a distribution span of 0.33, and high encapsulation efficiency (98% ± 1% and 92% ± 3%, for catechol and biophenols, respectively) were produced. The release of biophenols was also investigated. Full article
(This article belongs to the Special Issue Membrane Emulsification)
Figures

Figure 1

Review

Jump to: Research

Open AccessReview Linking Findings in Microfluidics to Membrane Emulsification Process Design: The Importance of Wettability and Component Interactions with Interfaces
Received: 29 February 2016 / Revised: 18 April 2016 / Accepted: 5 May 2016 / Published: 11 May 2016
Cited by 6 | PDF Full-text (2579 KB) | HTML Full-text | XML Full-text
Abstract
In microfluidics and other microstructured devices, wettability changes, as a result of component interactions with the solid wall, can have dramatic effects. In emulsion separation and emulsification applications, the desired behavior can even be completely lost. Wettability changes also occur in one phase [...] Read more.
In microfluidics and other microstructured devices, wettability changes, as a result of component interactions with the solid wall, can have dramatic effects. In emulsion separation and emulsification applications, the desired behavior can even be completely lost. Wettability changes also occur in one phase systems, but the effect is much more far-reaching when using two-phase systems. For microfluidic emulsification devices, this can be elegantly demonstrated and quantified for EDGE (Edge-base Droplet GEneration) devices that have a specific behavior that allows us to distinguish between surfactant and liquid interactions with the solid surface. Based on these findings, design rules can be defined for emulsification with any micro-structured emulsification device, such as direct and premix membrane emulsification. In general, it can be concluded that mostly surface interactions increase the contact angle toward 90°, either through the surfactant, or the oil that is used. This leads to poor process stability, and very limited pressure ranges at which small droplets can be made in microfluidic systems, and cross-flow membrane emulsification. In a limited number of cases, surface interactions can also lead to lower contact angles, thereby increasing the operational stability. This paper concludes with a guideline that can be used to come to the appropriate combination of membrane construction material (or any micro-structured device), surfactants and liquids, in combination with process conditions. Full article
(This article belongs to the Special Issue Membrane Emulsification)
Figures

Figure 1

Membranes EISSN 2077-0375 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top