Issue Date: June 9, 2008
Multiple Components Individually Wrapped
An electrospray method developed by Yong Zhao, Lei Jiang, and coworkers at the Chinese Academy of Sciences in Beijing can trap and keep separate multiple components in a single cell-like capsule in one step (J. Am. Chem. Soc., DOI: 10.1021/ja801803x). This technique could lead to applications in drug delivery, materials science, and food science. The researchers first embedded multiple capillaries into a needle to form a compound nozzle. They then fed a viscous inorganic “shell” fluid through the needle and up to four different organic “core” fluids through the capillaries. The shell and core fluids formed a compound fluid as they met at the nozzle’s outlet. Under an applied voltage to the nozzle, the compound fluid stretched and fragmented into a spray of charged droplets that formed into larger capsules. Droplets of each of the core fluids ended up with a “jacket” of shell fluid, which kept them separate from the other components in each capsule. In one test, the researchers used their one-step apparatus to separately encapsulate three different glycerol-based fluid droplets in a photopolymer shell. Previous methods to enclose multiple components in this manner required numerous steps and couldn’t always keep the components separate, the researchers note.
- Chemical & Engineering News
- ISSN 0009-2347
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