Because of the capacity of generating homogeneous and uniform droplets and emulsions, microfluidics has emerged as an attractive configuration for cell cultivation, screening and sorting. As a leading service provider in the field of microfluidics, Creative Biolabs possesses enriched experience in the development of microfluidic chips which are fabricated to generate stable and monodispersed double emulsions.
Double emulsions are liquid dispersion systems in which an emulsion of the dispersed phase itself contain even smaller emulsion, producing double-layered liquid droplets. Typical examples are water-in-oil-in-water (W/O/W) and oil-in-water-in-oil (O/W/O). These structures have shown great potential as compartmentalized systems to encapsulate multiple components for protecting bioactive agents (such as hormones, peptides and oligonucleotides), targeted delivering and controllably releasing drugs. Besides, various industries, including cosmetics, foods and pharmaceuticals, are showing increasing interest in double emulsions.
With wide applications in material synthesis, disease diagnostics, biosensors, protein crystallization, gene expression, drug and gene delivery, single-cell analysis, etc., microfluidics has shown great potential in double emulsion production. Compared with the typical two-step emulsification process for double emulsion production, the major advantage of microfluidics is precise control of droplet size and number by adjusting the flow rates of fluids, resulting in the controlled encapsulation of highly monodisperse drops. They can provide 100% encapsulation efficiency and accurate control of the size, number, shape, internal structure of the emulsions.
Fig.1 (a) Schematic diagram of the formation of a W/O/W double emulsion; (b) one-chip module (left) and two-chip module (right). Win: internal aqueous phase. O: intermediate organic phase. Wex: external aqueous phase. (Nisisako, 2005)
There are three major geometric chips to generate droplets with microfluidics, namely co-flowing, flow-focusing, and T-junction. All these three techniques have been adapted for the formation of double emulsions. Usually, combining two drop-making geometries to produce double emulsions is the simplest and most widely studied method, such as the succession of two cross junctions (flow-focusing). Lao et al. developed a new microfluidic platform for double-emulsion production which integrates T-junction channels, moving-wall structures, and a flow-focusing structure. Firstly, inner water-in-oil (W/O) single-emulsion droplets were first formed at a major T-junction. Secondly, the droplets were sub-divided into smaller uniform droplets by passing through a series of secondary T-junctions (branches). They skillfully use the moving-wall structures beside the secondary T-junctions to control the number of the sub-divided droplets by selectively blocking the branches. Thirdly, double-emulsion droplets were formed by using a flow-focusing structure downstream.
Microfluidic devices offer an alternate and versatile route to produce double emulsions. With years of experience and advanced microfluidic platforms, Creative Biolabs is continuously optimizing our microfluidic devices for the production of double emulsions with high yields, narrow drop size and size distribution, and high monodispersity. Our microfluidic chip can precisely control the size and number of inner drops as well as the size of outer drops enabling fine adjustment of the component dosage in the double emulsions for optimizing their encapsulations. The coefficient of variation (CV) value of the drops is usually less than 5% and the encapsulation efficiency is up to 100%.
Creative Biolabs is pleased to offer the best-qualified microfluidic chips with the capability of highly controlled and high-throughput double emulsion formation. If you are interested in our services, please do not hesitate to contact us for more detailed information.
For Research Use Only. Not For Clinical Use.