Such complex emulsions could be used to deliver ingredients in novel ways and at carefully calibrated quantities.
The researchers have fine-tuned the emulsion process in such a way that liquid can be suspended in another liquid with a third liquid layer around those. “This kind of control over the dynamic properties of emulsions could make it easier for scientists to tailor them to specific applications. The new method also enables rapid, large-scale production of such droplets,” Anne Trafton wrote in her article for MIT News about the development.
“They can also finely tune the configuration of droplets by adding different chemicals or exposing them to light or to different acidity levels,” Trafton noted.
Make it new
Suspending one liquid in another is not new (think vinaigrette). But having control over the process and being able to create emulsions at a scale useful for cosmetic and pharmaceutical uses is significant.
The MIT research goes further yet: “Traditionally it has been very difficult to create an emulsion that both encapsulates very robustly and releases in a controlled fashion. Here they have a very nice way to control the release, which solves an important problem,” David Weitz, a professor of physics at Harvard University, told MIT News.
And the researchers—Lauren Zarzar, Timothy Swager, Daniel Blankschtein, Vishnu Sresht, Ellen Sletten and Julia Kalow—have begun work on a next innovation: “They are now trying to develop surfactants that would be sensitive to other molecules, such as carbon dioxide or a specific protein, allowing the droplets to act as sensors for those molecules,” remarked Trafton.
Late last year scientists at the Korea Research Institute of Standards and Science announced a new technology for dispersing oil in water without the aid of surfactants. “The [ultrasound] device disperses oil particles in the water at such a small size by maximizing the cavitation, where pressure and high temperature,” reported BusinessKorea when the tech was announced.
“Since the device is designed to circulate in the solution, it can also evenly dissolve the particles. The process can be carried out on a large scale and automatically.”
And even more recently, University of Wisconsin-Madison scientists have been making strides toward a fuller understanding of the hydrophobic and hydrophilic qualities of surfactants. “We show that if you have two nonpolar groups, and they are going to interact through water, the way they interact depends on their neighbours,” Nicholas Abbott, a chemical and biological engineering professor at the University explained.