Recent advances in the production of controllable multiple emulsions using microfabricated devices

This review focuses on recent developments in the fabrication of multiple emulsions in micro-scale systems such as membranes, microchannel array, and microfluidic emulsification devices. Membrane and microchannel emulsification offer great potential to manufacture multiple emulsions with uniform drop sizes and high encapsulation efficiency of encapsulated active materials. Meanwhile, microfluidic devices enable an unprecedented level of control over the number, size, and type of internal droplets at each hierarchical level but suffer from low production scale. Microfluidic methods can be used to generate high-order multiple emulsions (triple, quadruple, and quintuple), non-spherical (discoidal and rod-like) drops, and asymmetric drops such as Janus and ternary drops with two or three distinct surface regions. Multiple emulsion droplets generated in microfabricated devices can be used as templates for vesicles like polymersomes, liposomes, and colloidosomes with multiple inner compartments for simultaneous encapsulation and release of incompatible active materials or reactants

Formation and modification of dispersions using Shirasu Porous Glass membranes

This chapter deals with the production, properties, and macrofluidic applications of Shirasu Porous Glass (SPG) membrane. The first section provides an overview of the membrane microfluidic processes used for production and modification of liquid-liquid and gas-liquid micro- and nano-dispersions, such as direct and premix membrane emulsification with and without phase inversion, membrane demulsification, membrane micromixing / direct precipitation and micro- and nano-bubbling. In the last section of this chapter, SPG membranes are compared with conventional homogenisers and microfluidic drop generators in terms of production rate, droplet size uniformity, and applied shear stresses. The second section deals with the fabrication of SPG membrane by spinodal decomposition in Na2O– CaO–Al2O3–B2O3–SiO2 type glass and morphological, mechanical, and hydrodynamic properties of SPG membrane. This chapter also covers modification of surface charge, contact angle and porosity of SPG membrane using different physical and chemical methods, such as deposition of silica nanoparticles onto membrane surface, coating with silicon resin, filling the pores with solvent-responsive polymer chains and chemical modification with silane coupling agents. The fourth section is focused on the effects of physical properties of the dispersed and continuous phase, operating parameters and membrane properties on the droplet size in direct and premix SPG membrane emulsification. In addition, the most common classes of micro- and nano-particles fabricated using SPG membrane were reviewed and their fabrication routes were discussed. It was concluded that a broad variety of different chemical and physicochemical processes can be combined with SPG membrane emulsification to convert droplets into uniform particle. The last section briefly discusses the generation of micro- and nano-bubbles using SPG membrane

Noncovalent interactions in microfluidic devices

Noncovalent interactions in microfluidic device

Production of nanoparticles using membrane contactors and microfluidic devices

Production of nanoparticles using membrane contactors and microfluidic device

Encapsulation techniques

Encapsulation technique

Biocatalytic membrane reactors

Biocatalytic membrane reactor

Controlled production of emulsions using membrane and microchannel technology

Monodispersed emulsion droplets are advantageous in both fundamental study and practical applications. Two main manufacturing approaches for production of monosized droplets are: (a) direct drop-by-drop manufacture, and (b) passive droplet break up in a confined geometry. The typical examples of the first approach are: (i) direct membrane emulsification (ME) [1]; (ii) microchannel (MC) emulsification [2], (iii) direct generation of droplets in flow focusing microfluidic devices and in microfluidic devices with T-junctions [3], and (iv) nanoliter injection. The examples of the second approach are: (i) premix ME [4], (ii) droplet break up in MCs containing T-junctions or obstacles [5], and (iii) droplet break up in micromixers. This lecture aims to introduce the latest development on the utilization of the membrane and MC emulsification techniques to the controlled production of emulsions

Biocatalytic membrane reactors (BMR)

Biocatalytic membrane reactors (BMR

Learning and teaching theory for engineering academics

Learning and teaching theory for engineering academic

Application of microfluidics and monodispersed emulsions to controlled release and digestibility studies

Application of microfluidics and monodispersed emulsions to controlled release and digestibility studie